This review may contain spoilers. I can handle the truth.
So I have *one* gripe: How the hell were they switching bodies for weeks (if not months) and NEITHER of them noticed they weren't living in the same year?? I guess you can hand-wave this away with space-rock-magic, but of alllllll of the things you're expected to do that for, this one feels the closest to contrived.
Other than that, this movie is a goddamn masterpiece of Japanese animation. Can't wait to see how J.J. Abrams fucks it all up with the live-action remake.