There is no game on this list or this year even that has benefited from post-release support more than Dawn of War 2. Empire: Total War may have been a broken mess on release, but when it worked it was still fun and still easily a candidate for the #2 slot. Killing Floor may have gotten boring because of its small map selection, but its core mechanics were still damn fun. Demigod's online situation may have been horrible on release, but 77% of Demigod players didn't care because even with bots the game was fun even if it wasn't reaching its full potential. Sure, Killing Floor and Demigod may not have made this list, but unlike Dawn of War 2 they would have at least been viewed positively still. Dawn of War 2, without the updates it has received, would have been a blight on Relic's stellar record only a tad smaller than The Outfit. Relic has stepped in to fill the strategy void that Blizzard has left since releasing WarCraft 3: The Frozen Throne, and Relic have stepped up to nigh indisputably claim the title of *the* RTS developer of this decade. The original Dawn of War legitimized the introduction of capture points as viable macro resources in RTS games and proved that squads were viable. Company of Heroes then took those innovations and transported them into an environment with an almost FPS level of detail and polished them to no end, creating the greatest RTS game of this century. With Dawn of War 2 coming from such a grand pedigree, it had little margin for error. On launch, it had errors.
It's still not without error either. The singleplayer campaign, in my honest opinion, failed to live up to expectations. It is a massive improvement over Dawn of War: Dark Crusade and Soulstorm's campaigns. However, while it avoids the complete doldrums that those devolve into, it does drag on a bit. It does not live up to Company of Heroes. Narratively, it's better than Company of Heroes, but still not great. However, the last mission temporarily brushes with greatness, tapping into the core of the WH40K license, but it pulls some deus ex machina and backs off (this isn't much of a spoiler because they've already made it well-known that your squads transfer into Chaos Rising). Still, for an RTS, the SP campaign is not bad and for fans of DotA and isometric RPGs, it may well be extremely enjoyable. I do prefer it to the standard RTS campaign structure of skirmish battles with cut-scenes before and after.
During beta and at launch, DoW 2's multiplayer was supremely disappointing. Relic had regressed to Dawn of War 1 combat depth while, at the time, having removed a fair amount of macro depth as well. They had scored points with heroes, particularly the Tyranid Ravener Alpha and Eldar Warp Spider Exarch, but DoW 2 was not supposed to be competing with DotA and Demigod and etc- it needed to compete at least with WC3 (excluding WC3's custom maps, although Relic really needs to consider the kind of success Blizzard has had with such functionality). Between meh battles and slow macro, DoW 2 looked to be a failure. Worse, what it brought to the table over Company of Heroes was melee combat, and at launch the game was not taking advantage of this distinction much at all.
But somehow, Dawn of War 2 rose to #1 on this list. Not only that, but I rate it as the third-best strategy game of all-time, behind CoH and StarCraft. So something significant happened at some point to elevate it to that great height. That significant occurrence was patch 1.5, aka "There Is Only War". The patch infused the game with a flood of new maps, including the superb Calderis Refinery which continues to be one of the best maps for all modes (1v1, 2v2, and 3v3). More importantly though, the patch completely reworked Dawn of War 2's balance. Relic freely admitted to having originally screwed-up, and in 1.5 they effectively fixed it.
What, exactly, did 1.5 do? It established the proper relationship between ranged and melee units, massively increasing the effectiveness of melee units and also increasing the overall lethality of combat. Dozens of units were also tweaked in significant ways, but I won't go into the details of that. The effect was massively deeper combat and finally Dawn of War 2's macro genius began to shine because of the more lethal combat. Do not let the lack of "base building" fool you- Dawn of War 2 has every bit of macro depth that Company of Heroes and other RTS games with "base building. Only when we get to the very elite macro titles in the genre such as StarCraft and Total Annihilation does DoW 2 begin to falter.
Dawn of War 2 consolidates the base building macro into four things- the HQ structure, the units, the hero, and the power. The HQ structure is the traditional base, like a Zerg Hatchery it has three tiers and each opens new units, upgrades, etc... There are two functions of this structure- to produce units, and to advance your tier. This is the only structure that can do these functions, so you need to plan its usage very carefully. What order you train units in is huge, as is the timing of your decision to research Tier 2 and Tier 3 (during those times, you cannot produce units and thus you potentially leave yourself vulnerable). This isn't, by far, where most of DoW 2's macro depth stems from, and Relic recognized that and that's the reason for the consolidation and it works.
Units and heroes are the bigger macro factors. In DoW 2, every unit in your possession represents a serious investment. In DoW 2, combat is almost unavoidable. It's nearly constant. The battle lines in DoW 2 are far more fluid than they are in Company of Heroes despite the smaller, tighter levels. It's a constant war to win the little battles, and it's here where the macro kicks in- it's embedded right in the combat. The main goal is to inflict more casualties on your foe than you take and to attempt to wipe out enemy squads without allowing any of your own to be wiped-out. Losing units in a squad is generally ok to an extent as they can be replaced relatively cheaply (it still takes a toll on your macro to replace them and it will delay acquisition of new squads and tier advancement, but you don't need to invest in completely new squads to replace dead existing ones), but losing an entire squad is often devastating. This used to be a rarity until 1.5. Now it's much more common. The other side of unit macro is investment in units. The only global upgrades in DoW 2 are Tier 2 and Tier 3. Otherwise, everything is local, and most units have upgrade options. These all tend to require power and requisition and purchasing them will delay your acquisition of other units- and, potentially worse, your upgrade to a higher tier. For example, Ork Shoota Boyz are pretty weak by default. However, for 75 requisition and 25 power you can upgrade them with a Nob Leader that turns them into a respectable ranged squad. You can also, for 80 requisition and 20 power, upgrade them with a Bigga Shoota which further increases their damage and grants them an ability, "Aiming? Wotz Dat?" which allows them to suppress a target enemy squad (very useful for keeping enemy melee units away and/or suppressing enemy ranged units while your melee units move in for the kill). Both of these upgrades massively improve the Shoota squad, but together they cost 145 requisition and 45 power. The second of these two stats is the big one because that is ~a third of the power you need to go to Tier 2, thus by upgrading even one of your Shoota squads you significantly delay your advancement to Tier 2. Now consider doing this for multiple squads. You'll get a short-term boost, but long-term you may have issues.
Heroes are similar. When killed, they require at least 250 requisition to resurrect. If you don't resurrect them, you're going to be working with less because the hero is a "free unit" per se (it doesn't factor into the pop cap) and heroes tend to provide the kinds of special functionality you need to make inroads against your opponent. For living heroes, you have the option of purchasing wargear. There are three types of wargear and usually at least three pieces of wargear for each type. These all cost requisition and power and thus pose the same issue as unit upgrades. Furthermore, many of these items are tier-dependent. As well, these items tend to open up abilities and functionality for your hero that can alter his/her role. For example, the Ork Kommando starts with a double-barrel bolter, marking him as a ranged unit. His damage is ok, but not extraordinarily, although he can prove very effective against light enemy ranged units and enemy melee units if he is microed to keep them out of range (a bit easier with good use of his stun bomb ability). In Tier 1, he can be upgraded with the Assassin Knife. This gives him a melee attack, allowing him to be effective in melee combat. It also makes him much more damaging against enemy heroes. This is further complemented by the Assassinate ability he gains, which allows him to deal a very large amount of damage in a single attack (this is analogous to gank/snipe abilities in DotA/HoN/Demigod/etc). Early on, this can prove very effective at countering enemy heroes (in particular, it's very useful against Space Marines because the Kommando can combine his Infiltrate ability with the Assassin Knife to engage Tactical Space Marine squads in melee combat without taking fire from them on the way there and then opening them to safe attack from your melee units; also, the Assassinate ability will kill a Tactical Space Marine and there are only three of them in a squad by default and they are expensive, so that is huge as well to gain a macro advantage). Later, the Tier 3 Rokkit Launcher often proves the more effective piece of wargear. This requires replacing the Assassin's Knife. In total, that's 80 power spent on the hero that can't be spent on advancing your tier or acquiring new units.
And power. I danced around that above for quite a bit, but power is big in DoW 2 because unlike in DoW 1, it's not in your base anymore. Relic took the fledgling concept of making power nodes capturable points (recall the super power nodes in DoW 1 that you could place your special beefy power structure on) and fleshed it out. Granted, this comes on the heels of Company of Heroes with its three types of capturable points (Manpower, Fuel, and Munitions). Power in DoW 2 is analogous to fuel in CoH or Vespene in StarCraft. It is the secondary resource that controls your ability to advance your tech tree and to acquire more valuable units and upgrades. It is, in the early stages, a very scarce resource whose usage has massive repercussions. For example, investing power in upgrading tier 1 units will help you dominate in tier 1, but if your opponent uses his/her power to instead tech to tier 2 and then invests in a vehicle, you could find yourself in a heap of trouble. Because power is forced to be on the field of battle now and no longer tucked deep away in your base, it is open to harass. Power harassing in DoW 2 is important and hearkens back to StarCraft in a very positive way. The system works as follows- when you capture a power node you start gaining a small amount of power per a second. Next, you can fortify the node (this costs 125 requisition) and increase the power gain rate while forcing your opponent to destroy the fortification before being able to capture the node. After a power node is fortified, you an add generators to it (100 each) which further increase the node's output. If you don't protect your power nodes, your opponent can destroy your generators and node and devastate your power economy. That's power harass. Your opponent can also just destroy the fortification and keep the generators intact and capture the node and they will then control the generators as well and thus they will use your investment against you (this is not as common as you'd think, as while it's a favorite of newer players to try this, in general players don't invest so much into power nodes that they do not have very good control over, so such fully decked-out power nodes tend to be close to the enemy's base and tough to hold and thus the enemy tends to recapture them quickly; slash and burn tends to be a more crippling tactic).
So all of the above combine to give DoW 2 a very, very pertinent macro element that is ever-present and which can often be match-deciding. I have taken such time exploring all of this because it was one of the biggest criticisms of DoW 2 initially because it was not implemented properly, but since 1.5 that has changed. Now, the game is much deeper and a ton more fun. The full capability of DoW 2's micro depth has now come to the fore and it's a very fun, eventful game to play. There is tons of combat constantly, often on multiple fronts, and you're kept very busy- rarely are there lulls. This makes DoW 2 a fair bit different from CoH and offers the different take on that formula that I think everyone wanted when DoW 2 was initially announced.
Beyond the above, it's also worthy of mention that DoW 2 plays extremely well in 1v1, 2v2, and 3v3. 1v1 retains the typical RTS showdown appeal. 2v2 hybridizes the intense competition of 1v1 with a bit of cooperation. Finally, 3v3 offers full cooperative play and the combination of heroes and races available in this allows for some real cooperation. Thus, the game has very wide appeal.
Despite the huge advancement that 1.5, There Is Only War brought, that was not DoW 2's only major post-release patch. Patch 1.8, Last Stand, was also massive in a completely different way. Besides further refining 1.5 (Last Stand made some additional, bold tweaks) and adding even more maps, Last Stand added... Last Stand. A brand new co-op survival mode. At first glance, this seemed to be the latest in a long bandwagon trend. But this is Relic, and this is a game that was not what it should have been at launch and they've been making up for that ever since. Simple pandering would do them no good. Last Stand isn't a bandwagon mode and it's not pandering. It's something that hasn't been seen much outside of the WC3 custom mapping community. Last Stand is rather highly-polished and quite fun. There are only three heroes available, but they're all diverse and fun to use. Unlike other games, the leveling system in Last Stand makes sense and is not pure grinding- it works nicely for the most part. Last Stand, on its own I have spent tons of hours with at 2am in the morning and a couple of friends. It's just damn good fun, and Relic did a great job rejecting what most developers do, which is using their core gameplay for every mode whether it fits or not. Campaign, Multiplayer, and Last Stand all use roughly different mechanics and all play very differently. They're like three different games based on the same engine instead of just three different modes. And Relic scores high points for this- there is almost assuredly something for everyone in DoW 2.
So, despite a slow start that saw lackluster MP and a horrifically small MP map selection, Relic have more than turned Dawn of War 2 around with a series of intelligent patches. For free, they have almost recreated MP from the ground-up and they have added what, on consoles would be a $15 piece of DLC with Last Stand. These improvements have made DoW 2 what it is today- the best game of 2009 and one of the best RTS games of all-time. I simply cannot wait for the Chaos Rising expansion now as it will be adding a new campaign that seems like it will fix some of the issues with DoW 2's campaign, it will add a new race (Chaos), and it will add two new heroes and a new map to Last Stand. And if all that doesn't work, Relic has established that they will do whatever is necessary to bring their game up to snuff.