iTunes for Mac users is not 64bit but for Windows Vista and Windows 7 is. What I don't get is whats with all the rush for 64bit? I like how apps load faster in 64bit but I think a lot of people are still misunderstanding what the point of 64bit is.
Also, I heard that Microsoft is planning a 128 Biit OS for Windows 8. Ridiculous in my opinion there is barely 64bit apps out yet and Microsoft is jumping ahead of themselves as usual.
Windows 8 / 9 is still far enough out that I'm sure they are claiming it will have WinFS and Duke Nukem Forever included. I wouldn't put to much stock in what they are claiming yet.
But even if they are working on 128-bit I can't say it's necessarily a bad thing. Looking forward is a good thing. It's better than them saying "No one will ever need anything beyond 64bit". In fact I would hope that enough lessons are being learned from the transition to 64-bit that all the OS makers out there will have a better time when it's appropriate to make the 'next step' I can't fault them (or anyone else) wanting to make use of the lessons while they are still fresh on their minds.