"Alien Swarm is a game and Source SDK release from a group of talented designers at Valve who were hired from the Mod community. Available free of charge, the game thrusts players into an epic bug hunt featuring a unique blend of co-op play and squad-level tactics. With your friends, form a squad of four distinct IAF Marine classes."
This thread pretty much explains my feelings towards valve
http://forums.steampowered.com/forums/s ... ?t=1364681
Game looks awesome and I can't wait for it to come out













