Probably fixed here: http://www.sacredchao.net/quodlibet/changeset/4230 .
Steps to Reproduce:
1. add a feed (in the "Audio Feeds" view)
(http://rss.dw-world.de/xml/podcast_zeitreise_nobelpreistraeger in my case)
2. play something from your normal music library, so that that information about
this song appears
3. play an item from the feed
the old information about the song is still displayed
the information is updated
Highly orphaned, indeed.