Yes, everyone else gets to experience it now (and there are some nifty changes, even on the Mac side). From what I've read, the Windows app is very nice, but also a memory hog. But no one I know is running it yet.
http://www.apple.com/itunes/ for the info and download.
the iTunes store has also added audiobooks (although not at $.99 or anything close to that cheap), including a nice collection of Peter David Trek books. And you can now access playlists from folks like Sting and Ben Folds and Moby.