absolutely love CoD4. much more fun than CoD2 i reckon, although I admit i am only talking about single player here. never played either in multi player.
CoD4 just seems to flow better action wise, it is always full on, running round, enemies popping up, firing fast etc. CoD2 felt clunky in comparison, really cliche situations really, you sit at the top of a house. enemys come in waves, waiting to be mowed down. v predictable. i still enjoyed CoD2, but CoD4 is somethin else entirely. love it