Not much leverage, if you notice that it still is a Japan exclusive. I figured they didn't think it would be much of a system seller outside of Japan anyways because if you look traditionally JRPG's don't do that well outside of Japan. So might as well get it to as large an install base as you can with both the PS3 and 360. To be perfectly honest I'd rather it on PS3 though because I wouldn't have to deal with the problems people ran into with Lost Odyssey and the multiple discs + freezing problems.

Edit: Forgot to note that Final Fantasy XIII: Versus is a PS3 exclusive still.