Album Artwork being 'funny' since 5.2.1?

My artwork was coming up fine in 5.1.
Starting today, with 5.2.1, the artwork looks generally fine on the main web app, but *some* artwork won't appear in any other context correctly. The server serves up the default two-color + text default artwork. This includes the right side "currently playing" and my SubFire client.
Any ideas? Nothing else in my env has changed.
And again, it isn't *all* artwork, but certain folders seem more affected than others.
Starting today, with 5.2.1, the artwork looks generally fine on the main web app, but *some* artwork won't appear in any other context correctly. The server serves up the default two-color + text default artwork. This includes the right side "currently playing" and my SubFire client.
Any ideas? Nothing else in my env has changed.
And again, it isn't *all* artwork, but certain folders seem more affected than others.