I also spent the day adding what I call "DoubleClick To Play." Double-click a song anywhere and it'll automatically start playing. If you already had a song playing it'll just shove that back onto the end of the queue. It's a neat way to quickly put together a playlist while playing music, because the queue effectively acts as a play history. After an hour or so of playing you end up with a nice little snapshot of the songs you like to hear. A quick Right Click -> Select All -> Add to Playlist saves them forever. And yes, part of this update was support for adding songs from the queue to playlists.
Also, there was a bug in removing songs from your library. Basically, the songs were removed from the library cache but a dumb sql typo meant they weren't being deleted from the database. That was fixed.
Also fixed a bug that wasn't correctly grabbing the ID3 song name tag from files, so the song names should actually display correctly now - assuming the file has ID3 tags.