I finally got around to play it on PS3 now... basically it's day and night compared to 360 version. Funnily there's some things looking better on 360, but generally the PS3 version is much more detailed and game play (camera) makes more 'sense' somehow.
I still don't get the fighting system entirely
however... do you really (really?) need to upgrade your weapons in order to beat some enemies actually? I think it gets much too difficult much too fast, kinda frustrating. :/
As said before, 360 version still looks very good. My guess thanks to the ATi card, it looks almost smoother, too.
Personally I'd never ever buy a Nividia, but that's just me...