A well documented problem so far.
Would just like a DEFINITIVE answer
- Running iTunes 10.5.3
- Lion 10.7.2
- iTunes Match working great with songs still stored locally.
- Have re-downloaded all album artwork & displays just fine while in iTunes
- When activating Screensaver, get the message 'No iTunes artwork found'
Ok all you mac/iTunes geniuses, what have you figured out so far?
I had the same problem followed all of the steps mentioned above and none of them worked.
I got it working by recreating the itunes library; you can find all of the steps here: http://support.apple.com/kb/HT1451