It would appear that the RSS reading stuff in Thunderbird is a bit buggy. The primary problems involve the removal of feeds. If you remove one, it puts it in the trash. If you empty the trash, the trash folder goes away too. Then when you restart Thunderbird, the feed is listed again, but there aren’t any contents. It’s not listed when you go to Manage Feeds, so you can’t remove it again.
I’m sure they’ll clean it up, it’s a good feature.
