PUBLIC MARKS from dfracheb with tags apple & itunes

iTunes 7 can fetch album art also for tracks that were not bought from the iTunes Store. A lot of users, including me, have themselves added album art from a third party location (such as some web site) to tracks that were ripped from CDs. Often this is of quite poor resolution, and it would be nice to replace it with a version from the iTunes Store. Unluckily, this artwork prevents iTunes from fetching a replacement.