Rythmbox successfully downloads all album metadata, I think from musicbraiz. However I recently put in a disc when my network was dead. It failed to find the data, of course, with a fail message, but I can't find a way to make it try again, now that net is back alive. It's not automatically trying again. The data exists on musicbrainz, checked by searching for it on website.

Ubunut 12.04
Rhythmbox 2.96