This is an article I found: http://www.eyeballistic.com/?p=415
Sorta makes sense... but not that much. I wonder if it's resolution too? Most PS3 games run at max 720p, right? Whereas a PC game must be capable of running at 1080p or higher, so the graphics can't be as extreme, or it'll cripple any reasonably high end system. Maybe that's nonsense, I dunno.