Hrm. The game looks slightly worse than the 360 version, at least to me. I think a large part of it might be that Bioware was just using more than 256megs for their GPU ram, on average.
[ss]If you look at the comparison shots, it's not just that ME2 PS3 is brighter, although that's a part of it, but if you look at things like the eyebrows you can see how they look slightly blurrier and larger on the PS3, and that's a sure sign that the res and such is lower.[/ss]
Actually it might just be the brightness+ lowering the color depth on the textures?
A huge ton of frame hiccups and screen tearing on the demo as well, but that might just be a demo thing.
I had fun playing the demo, but considering I have the PC version, a new lighting engine isn't enough to get me to buy the game again at 60 dollars.
ME3 probably won't have as many problems running on the PS3 as a port over of ME2 does, still, the hiccups and lower res textures are disappointing.