I don't think people realize this yet. But the PS3 stopped being the "lead" console of Final Fantasy XIII about 2 years ago when Square said they're porting the white engine to the PC/360. It was even announced at E308 when they announced the 360 version, that the game stopped being made on the PS3 and was being made on an nvidia PC workstation. The nvidia page that had this information is down, but this forum says the justs of it: http://www.nvnews.net/vbulletin/showthread.php?t=116702. So as far as the 360 version of Final Fantasy XIII "running" worst than the PS3 version, you shouldn't worry. It'll probably run better actually. There's a video somewhere on the interwebs of some people breaking down the game with framerate and such to see how it'll fair on the 360 and with all the alpha blending the game was running it'll probably run better on the 360. Though they did mention the game's using the high end HDR that the 360 isn't capable of so the lighting will be unnoticeably worst. Though I would still suggest the PS3 version if possible for ease of use. Or the PC version that they're sitting on but not releasing.
