If you accidentally clear a playlist that you wanted, there is currently no way to bring it back. I think we should cache off the previous 10 or so playlists that can be called back

pseudo spec:

whenever a playlist is cleared for whatever reason, save the playlist named with a timestamp

save the previous 10 or so playlists

in the Music Library->Playlists menu, there is an item for something like "recent playlists". Drill into that and you get the list of recent playlists, most recent at the top