Although I'm done with iPods (not buying any more once my current ones die), I still have an account with iTunes, and one of Windows boxes is still authorized, so I went to check it out. Indeed, the situation with J-Pop has imporved dramatically. I ended getting some Hiromi, Ayumi Hamasaki, etc. However, Rie Tanaka, Shogo Hamada, and a few others are missing still. Most important gap, I think, is Judy and Mary.

UPDATE: DiGiKerot says that KOTOKO is available in U.K.. Grand. Oh wait, I have her CDs, I don't need DRM-ed music...