In case anyone thought that I was a fan of the game or anything, here's what a real fan is like: "three sets of the alternative sleeves for the game" (with pictures!). Sadly, judging from the YouTube videos, the PSP version is animated much worse than 360. DiGiKerot puts a positive spin to it though:

PSP iM@S is actually a pretty good game. Obviously it doesn’t have the visual fidelity of the 360 version - it’s cel-shading is entirely faux, achieved using fixed pre-shaded textures and a lack of lighting, and its frame rate does tend to stutter a little when there’s two characters on display during the dialogue sequences - and the fact that you can only manage one character at once kind of stings, but from what I’ve played so far, everything else seems like a step-up from the 360 version.

Still, even if I wanted to play this, I probably would not bother, what is with all the firmware and region issues. My daughter has an ancient PSP that has gone into a semi-retirement after I got her a DS, and I even inquired about borrowing it. But the uncertainty is too great, and in any case I'm not a gamer.

UPDATE: DiGiKerot e-mailed that I'm just confused and there's no region coding for games, only for UMD movies.

ON SECOND THOUGHT: I lookead a screencaps at Play-Asia and became convinced that with my Japanese, I would be getting way ahead of myself by attempting to play this. Otherwise, the game is eminently affordable (unlike a project of getting a whole Japanese 360).