Why would it be too late? The game doesn't come out until "Spring" for the Xbox 360. While that could come out at the beginning of March it may not be released until June. I'm hoping they use a solution like the one I mention above but since this game has lead on the PS3 I don't think PS3 owners have anything to worry about.
1. I think the pipeline for a game like this is too long to do anything significant in these terms in its last year of development, particularly with the game so close to release in Japan.
2. The game is, as far as I know, developed primarily on the PC and then the (White) engine is ported to the PS3 and 360. This is partly why I don't expect a dual harddisk/bluray streaming system to be in place in this game. So in those terms, I'd actually expect most graphics (just about everything except the cut-scenes) to look better on the 360.