I'm a huge Left 4 Dead fan, and having played the pc version extensively, going to the xbox version is simply painful. Apart from 30fps instead of 60, I can't imagine anyone being able to do expert/expert realism playthroughs as it would be virtually impossible with a controller (Do any xbox l4d2 players here have the 'Still something to Prove' or 'The Real Deal' achievements and didn't cheat to get them? I'm seriously curious).
I mean there are several 100+ post threads dedicated to the differences between ps3/360 games. Most of the time it's a complete joke compared to differences that console and pc versions multiplats regularly have.
Demon's Souls Official Thread | Currently playing: Left 4 Dead 2, LittleBigPlanet 2, Magicka