I just upgraded my Macbook to iTunes 8 last night, and have had problems ever since. The album art for some of my movies didn't appear after the upgrade, so I tried re-adding them myself. However, after clicking "Get Info," the dreaded pinwheel came up and everything hung like that for about an hour. I couldn't even access the Apple menu to force quit! After that, whenever I try to play a movie in my library, the same thing happens - pinwheel, freezing for a few hours, nothing. This is really freaking me out. How can I fix this??? 