I have a 360 and a friend of mine has a PS3. We've been comparing, but neither of us have any of the same cross platform titles.
The only things I can note are that the PS3 games seems to take alittle longer to load, but again this is apples to lemons until we can find a common title. - Also, the PS3 controller feels a little light and flimsy to me due to the lack of vibration, but then the 360 Controller feels heavy to him
Can't really comment on the visuals, but we both agreed that GRAW2 on the 360 looked the best out of all the games we had on the two consoles.
Still early days though, and yes Resistance:FOM is pretty nice even though I only got about 30 mins with it.