I know for sure that it's playable on PSP, though, since I just bought it. Yes, that means I now own four "copies" of Wizorb--one each for my Mac, PC, PSP and Xbox 360.
A word of warning to those of you who are about to race to your PSPs and download this puppy: A bit of "frame-rate chug" weaseled its way into this particular version.
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It doesn't ruin the experience--or at least it hasn't yet ruined it for me--but it is noticeable, not to mention a tad annoying, especially if you've spent some time with the Mac, PC or Xbox 360 releases.
Hopefully no such "chug" rears its ugly head while playing the game on a PS3 or Vita. Since I don't own either of those systems, though, I currently can't tell you if that's the case or not.
See also: 'A somewhat gay review of Wizorb (PC and XBLIG)' and 'Ten questions with the guys who created Wizorb'