Right I've played all 3 versions and here is what I think. The PS3 version is the worst version but it's not quite as bad as I expected. Hard to put into text but if I say that the PC version (on my PC) is 100%, then then Xbox 360 version is 80% and the PS3 version is 60%. The PS3 version looks the worst and runs (FPS) the worst.
Saying that, on a MP game such as this, you don't get time to look at textures, it's all about kills/deaths. It might widen the gap if the SP game is slow paced and you explore etc.
for me, I'll probably buy the game on the Xbox 360 when it reaches that magic £17.99 price in a couple of months to play the MP and then buy it on the PC in a steam sale to play the SP at christmas.
TBH I can't see the point of this game. It has very little to do with Crysis 1 and it's never going to compete with COD.
£17.99 or less and it will be worth a laugh for the odd MP game on the Xbox 360 with a mate.