Apple has done a terrific job porting iTunes to the Windows world. I had no installation problems, and was up and running, and sharing across my home network, in a couple of minutes. But now it turns out that a college student has hacked iTunes for Windows to allow users to download tracks on other users shared playlists. It's reminiscent of a bug (or feature) in the first release of iTunes 4.0 on the Mac, which allowed the same sort of sharing over the internet, and not just on local networks.
Apple has done a hell of a lot of work to try and legitimatize the purchase of music online, but they're going to run out of good will from the record companies if they keep putting out software with loopholes like this. Look for a "bug fix" soon.