I'm currently playing Colonial Marines, and really enjoying it. I don't get the hate, and some of the critisicms seem a bit odd. "Oh, you fight enemies with guns!" Well, that's what the USCM mainly do. "The AI never kills anything!" If they don't, how do I get assists on single player? "Why do the aliens just charge towards you to be shot?" Did you actually see the sentry-gun sequences in Aliens
Only criticism I really agree with is that the E3 'Gameplay' footage WASN'T actually from the game at all.