I'm not denying that Half-Life had more of a historical impact on the gaming community, and that it wasn't almost revolutionary but that doesn't stop the fact that today, at present, Half-Life 2 is a better game. I think we're getting to an age now where there is little to do to innovate (Particularly in the FPS genre) other than to better the things we already have. Half-Life 2 did this dramatically with it's insanely good physics and graphics and the innovative gravity gun.
Anyway,
Halo 3 FTW!