I used the submit feedback to Apple link in iTunes.
http://www.apple.com/feedback/itunesapp.html. I am not sure if there is a seperate link for bugs though, I couldnt find one. I imagine with enough reports they will look into it. I don't think it was either brought to their attention in time (or they either didn't figure out the solution yet) by the time of 10.2.1's release, as it was very fast.
Unless (I really hope this is not the case though) that running 10.2 did something irreversible, which a hotfix could not solve. But I also doubt that too. I'm sure a iTunes update or a minor OSX update could fix it.
This is something else I noticed too: check your iTunes Library folder. The individual file icons in Finder used to have the album art as their file icon. Now, most of my items are just the standard iTunes file icon (the page with the logo and format written on it). I wonder if this has something to do with it. Oddly enough I liked the album art icons too there.