I logged on using the PAINFULLY slow Russian internet just to say that Keero is wrong. Dawn of War 2 is a lot of fun, but the original is worth playing for sure, definitely invest in it. It didn't suck up hundreds of hours from my life by being a bad game. You don't need it to understand the story, but the multiplayer is still more fun in the original if you can find a game.
I preordered the Collector's Edition. I couldn't make up my mind as to what pack I wanted, so I got them ALL. Also I'm a sucker for the poster and cards that tends to be included in CE boxes...