Hard to say really... comparing static screenshots is kinda pointless. It's no Crysis, but it looks great when moving. Just take the helicoper tour at night or a taxi ride through Star Junction and you'll agree.
You could say the 360 version is "sharper" or you could say it is "jaggy"
You could say the PS3 version is "blurry" or you could say it is "smoother"
It's personal preference but I doubt you would even notice at normal playing distance on a normal TV when the game is in full motion with moving, shooting, driving etc.