The following article is an interesting read:
http://www.eurogamer.net/articles/digit ... ps-faceoff" onclick="window.open(this.href);return false;
It looks like the xbox version is better in pretty much every way, including 3D.
I don't think it really makes any difference the resolution that the TV detects since all the consoles (well, xbox360 and ps3) have hardware scalers anyway. For example, Halo Reach, the TV detects it as 1080P, but up close, you can see that this isn't the true resolution.
If my TV comes today (and has glasses with it), I think I'll get the xbox version to try out.
Chiefwinston - With the PS3, can you change the screen size on the PS3 (not in the game)? If you can, have you tried setting the screen size SMALLER then the tv is and see if it makes the 3D effect more pronounced?... Just a thought.