I installed iTunes 5 on my Windows 2000 PC, upgrading from iTunes 4.9. The upgrade killed all my podcast subscriptions. While installing, iTunes said my library was damaged, but my music does show up. It looks like it is all there.
Also, the upgrade damaged some of my smart playlists. Any rule in a smart playlist that references another playlist is damaged, so in addition to adding back podcast subscriptions, I have to fix many of the smart playlists.
Upgrade at your own risk!
UPDATE: Two more problems.
1) iPodder no longer talks to iTunes. So that means the podcasts that iPodder downloads is not updated in iTunes. Makes iPodder useless. I bet Apple changed the API.
2) iTunes doesn’t recognize either of our iPods, so we had to reload everything back to the iPods.