Well the original Killzone was a response to Halo 2.
And since that sucked so hard, I guess you would technically call Killzone 2 a response to.............Halo 2.
Haha, killzone 2 combated halo 2 with a cg trailer. Kz2 is more of a response to halo 3 and gears 2.
Honestly, KZ2 looks good. The controls look weird, but the game looks solid. I'd definitely buy it if I didn't have to get a ps3 first. Unfortunately, this game is way to late in the race to be "all that". If this game came out last year or even the year before, it would set the bar for triple A games. This game just lacks originality like most FPS's.