I've been playing a fairly huge amount of Dawn of War II over the weekend, and I think it's really rather good.
The original Dawn of War was pretty much my only exception to my "RTS games all suck" rule (though there are a few other notable exceptions, such as Haegemonia: Legions of Iron and Star Wars: Supremacy), so I was looking forward to this. The first surprise when playing the main campaign of Dawn of War II was that they've done away with base building altogether. You start each mission from a drop pod and the missions themselves are much shorter and more focussed than in the original game. You also only have a handful of squads to play with, rather than a squad cap, meaning that rather than having eighty-odd Space Marines and assorted armoured units rampaging around the map in a couple of groups sweeping aside all the opposition in their way, instead you've only got around a dozen people in four squads, and the squads themselves are much more specialised, making battle management much more like an RPG than an RTS, as you have to use each squad in a way that plays to their strengths, rather than just standing toe-to-toe and letting the people with the biggest boots win the shin-kicking contest.
The move to a much more tactical combat model (with it's traits, accessories and abilities for the characters leading your squads) makes the game a lot more involving than the original, and employing your people properly is all the more important, because unlike the original game, you can't reinforce at will by clicking a button. You have to be near a control point or building you own in order to replace slain personnel, which encourages you to take a greater level of care in engagements, because careless losses really are punished.
There's also a greater emphasis on completing levels quickly, as you're graded not just on how many enemies that you kill, but also on how fast you achieve your main objective for the mission; so rather than having missions lasting an hour or more, you can complete most missions in under 20 minutes. I don't think is such a bad thing, as it means you can progress through the campaign relatively swiftly, and there are a greater number of missions to play than in the original game, so despite the shorter level length, there's enough going on as you flit from planet to planet throughout the sector that you're not going to feel too short-changed.
From this point on, Here Be Spoilers, so consider yourself duly warned...
The game starts innocently enough with you slaughtering Orks on the Blood Raven's homeworld as you put together your team over the first few missions. First it's just you (the Force Commander, who occupies one of the four squads by himself, due to his resilience and ability to kick alien butt) and Tarkus, a former Terminator who now leads a standard (bolter-equipped) Space Marine squad. Over the next few missions you get to meet Cyrus (a Space Marine Scout), Avitus (a Devastator Marine) and Thaddeus (an Assault Marine) and their respective squads, all of whom join your merry band of killers, though you have to pick and chose which of these squads you leave behind, as you have four to pick from, but can only take three along. (I'm assuming at some point you get the option of bringing along a Dreadnought, too - but I'm not quite that far in yet)
I've mainly been playing with Tarkus, Avitus and Thaddeus, leaving Cyrus behind, as Cyrus is very weak in melee, so not really suiting to fighting at close-quarters, and his ranged damage isn't nearly so good as that you get from Tarkus or Avitus. The infiltration ability is pretty handy in places, but I don't think he's quite as useful as the other squads. Tarkus is good to take along mainly because he has a shitload of accessory slots, which allow you to use support or attack items in combat (such as health packs, melta-packs or portable turrets) and his ranged damage is decent enough, especially if you pick up improved bolters or plasma rifles in the random loot drops. Avitus and his Devastator squad are pretty much compulsory in my eyes, since the sheer firepower you get out of those heavy bolters is amazing. If you set them up in cover (or better yet, a building) and get the Force Commander to pull enemies towards their position, it's like a shooting gallery - and the sound you get from those heavy bolters is terrifically satisfying. But I think my favourite squad is Thaddeus's, as getting him and his Assault Marines to perform hit-and-run attacks using their jump-packs is just awesome. Each squad has its own niche, and if you co-ordinate them correctly, you can really clean up. Orks especially don't stand much of a chance if you use Thaddeus and the Force Commander to draw them into ambushes.
The early levels aren't so challenging, but once they introduce the Eldar (who have basically plotted to send the Orks into the sector to help slow down the Tyranid advance, only for the Space Marines to foul things up by duly slaughtering all the Orks), things start to get much tougher, and you really have to pay attention to the deployment of your squads and not let one unit get isolated, or they'll get slaughtered. Vehicles, such as Fire Prism Tanks, are a hell of a lot tougher than they were in the original Dawn of War - or maybe it just seems that way, since you've only got a handful of people to command now. Each mission usually ends with a bit of a boss fight - ranging from the fairly easy to the rat-bastard hard - the Eldar Wraithlord encounter in particular is a really nasty fight, as you have to be really careful with your squads and not let the bastard get too close for insta-kills in melee. Fortunately, to offset the low number of troops you have at your disposal, Relic have implemented gear upgrades, which take the form of random drops of weapons and armour, in a World of Warcraft-esque white/green/blue item ranking system of rarity and power. (If they have purples - i.e. epics - as well, I've not found any yet) Your squads also accumulate experience during combat and can gain levels (to a maximum level of 20) and assign skill points (2 per level) into ability trees (Health, Energy, Ranged Combat and Melee Combat) to unlock extra traits, some of which give talents and abilities to be used in combat, or allow characters to use special weapons, like Power Fists and Flamers.
By the time the Tyranids turn up, you should be around halfway up the level tree and will have upgraded the gear on all of your squads to stuff substantially better than what you start with, and it's really necessary, because they're pretty fearsome. The first time you fight a Carniflex is pretty bruising experience, and while the Eldar are pretty annoying in great numbers, the Tyranids are even more so, since you get swarms of the fuckers spitting gobs of acid at you from beyond Devastator range. Once you get your tactics sorted, though, you can deal with them without too many problems, though I do expect things to ramp up a bit more when the Tyranid infestation levels start to peak later in the campaign.
Overall, it's great fun and I've found the single player more direct and involving that its predecessor, though it does perhaps lose a little on spectacle, because you've got fewer units to play with. But I'm pleasantly surprised that Relic had the balls to not simply make Dawn of War with shinier graphics and Tyranids. Anything that will upset genre purists and fanboys gets my vote. I reckon I'm only about halfway through the campaign (7 hours played so far, according to my Steam page), so I've still got a fair way to go with this, but from what I've played so far, I think it's well worth the £23 Play are asking for it.
My advice? Go buy.