Haven't had to type that many subtitles since I told someone about TWEE:DC :p
This came out last week. I actually pre-ordered it and planned to play on launch, but I forgot that I hadn't done the campaign since before I upgraded to Win7. So rather than try the default FC, I just replayed the campaign. Very enjoyable, made me realize that the Dreadnought is much more fun than Avitus (albeit, a lot more vulnerable due to vehicle health).
But I digress.
This expansion adds:
Epic levels for the Astartes, and lots of new traits/abilities to go with them. Stuff like Tarkus getting to be a Sternguard, The Dreadnought getting to be a mobile base (for all intents and purposes), and even more shiny for Thaddeus and The FC.
Lots of new toys. I already see a grenade launcher for Cyrus
Chaos: Yup, the forces of Chaos are finally here. Their heroes are Chaos Lord, Sorceror, and some Nurgle-flavored champion. Bonus points for not fielding a Bloodthirster. They field a Sorc for Last Stand.
New Units for everyone: Yup, the Blood Ravens (infamous for their high number of psykers) finally have a Librarian.
So far, it seems pretty fun.
And one big point of notice: When you start the game, even if you import your DoW2 char, you get a notice saying that lots of wargear and relics were lost. This is then followed by you starting a mission with a default loadout. Do not be alarmed, it looks like most of the gear is still there. They just make you start with axe and bolter, rather than Daemonhammer or Termie gear.
So seems well worth the price thus far. Now here is hoping we get IG and 'cron in the next expansion pack.

IG are a certainty at some point. Also GW are supposed to be updating the Dark Eldar at long last (12 years since they had any love!!) so you can expect to see the spikey spaces elves sooner rather than later.
My only real issue with Relic is we were promised Eldar and Ork campaigns and still nothing. I for one simply get bored playing Space Marines.

I'd love a Tau campaign. I had a lot of fun playing them in the original Dawn of War. But all things considered, I'm very pleased with the DoW2 expansion. A lot of quality content thar.

My copy of Chaos Rising has not arrived yet, but I am enjoying the new toys the patch brought to everyone (Weirdboy rocks! New and horribly OP Wraithguards and Assault Terminators with claws....yay!).
Out of frustration I have started new campaign on Captain difficulty while waiting for the game to arrive.

One would think the IG would be coming, since they are essentially already done (short of heroes), but I am just concerned as to whether or not they would fit with Relic's gameplay style. The IG-Astartes balance is VERY fluffed up and pretty, but as a result it would probably require much larger IG squads to stand a chance. So would be closer to a traditional RTS, not the tactical game.
Oh yeah, register DoW2 at THQ's website for some free wargear.

Uh, the Tyranids are also a "send hordes on them" faction like the IG, yet they are implemented in the game without much problems.
But to make it more feasible from lore point of view, in-game IG could be represented as elite strike force (Stormtroopers/Kasrkin, HWT, Ogryn, maybe Ratlings as a sniper unit, some walkers/vehicles), so IMO there would be no need of large squads. Add a few heroes like general/commissar/psyker for example and you have a complete faction.

No more Kasrkin ever! Please! They are Cadians. Stormtroopers are fine but I cannot understand Relic's love of Kasrkins.

Well, the Kasrkin could be commander dependent summon. One commander could summon Kasrkin, other Catachan squad and the last for example Death Korps or Penal Legion squad - each commander could come from another regiment.

I just want them out full stop. Every second they are in a Relic game it ruins them. Kasrkin are utter nutcases, they are like the Sardaukar in Dune. Quite frankly a Kasrkin could rip off a Marine's arm then beat him to death with the wet end. In Winter Assault they were used as just Stormtroopers, it was a disgrace

I would go nuts for an IG expansion, heck make a special ability called 'reinforcements' so that each IG guardsmen that dies makes 2 pop back up in his place for like 10 seconds for say the Commisar, then bring back the good old execute ability to make them fight harder. That way you could do a one-two punch, reinforce your guys for 10 seconds then when that wears off make them fight harder for a little bit with the extra numbers.
Above would be cool but I can make do for new expansion for now. I seriously love the game since I got it on the THQ.uk deal for 5 pounds, reminds of of XCom the RTS.

Have the graphics & effects been upgraded by much? I'm interested in it but the core game on minimum detail runs at maybe 15fps and any more pretties will likely make my poor old laptop catch on fire

It's been basically integrated into DoW II. So if you still can run it, chaos rising will probly run too :D Didn't play the campaign yet thou...

Now only if i liked DOW 2.
Well i don't HATE it but if you ask me the first was much better (Including expansions up to DC). The whole special forces minor unit commanding thing does not bode well with me. I don't mind last stand but i feel i will lose interest any moment. Plus DOW 2 doesn't look THAT good, just pop Fire Storm over Kronus into DC and bam, sexy DOW 1.

Really? I was under the impression Kasrkin was just a fancy name for Cadian Stormtroopers. Of course, I only have the 4th edition book on hand, where the Cadian 8th are special in that they have 7 instead of the maximum 5 doctrine thingeys....
But yes, I think calling them Stormtroopers would be better, especially since the player can use different uniform colours for multiplayer. :)