I'm seeing fairly consistently inconsistent behavior when syncing mp3s to an ipod (classic) running the 1.1.2 firmware.
The general problem is that I run a sync, then immediately after finishing, I do a "recheck sync" and it sometimes comes up with more files it wants to sync.
The latest go was paying more attention. I wiped the ipod all the way back to the point where I need to re-enter my preferences like language and so on using itunes. Then did a sync, so it copied over my entire library. Immediately did a re-check sync and it reported about four Pink Floyd albums that it said it needed to sync. So I hit "recheck" again. This time there were those Pink Floyd albums, plus two more unrelated albums. So, hit "recheck" again. Okay, back to just the four Pink Floyd albums. At this point, every "recheck" gives me the same set of albums that it wants to sync.
So I went ahead and let it run. Then I noticed in the list after it finished that the albums appeared twice. Checked the ipod. Sure enough, they're there under artist Pink Floyd, and there again under "Unknown Artist".
I can only find the one Pink Floyd instance in Media Center.