I'm in France for my wife's birthday for a few days and won't be blogging regularly, but I know a lot of people were looking forward to this, so what the heck:
iTunes 7.6 or later is supported with any 64-bit edition of Windows Vista. If you are using 7.5 or earlier, some features may or may not work correctly.
The question, of course, is whether this means the iPhone and iPod touch are now supported as well. I assume that is the case.