iTunes 4.5 is out. There are too many big changes to list, you should just go read them for yourselves. Don't get your hopes up too high, the DRM on the store is still in effect.

Update Thu Apr 29 09:20:11 PDT 2004: Just a heads-up, but I'm running into a problem sharing an extremely large library (19,000+ files) with 4.5 that shared just fine under 4.2. Both machines running 4.5 and the library will just not come across the network. A bug report has been filed.

Update 6/11/2004: Update to iTunes 4.6 for the fix.