I think the playlist feature would be used more if it was displayed in the left pane along with the music list. I was thinking it could be loaded like a podcast or internet radio.
Things to have loaded (column format) would be the playlist name (no need for extension part), load playlist, download playlist, Settings. The settings page would only be visible to those user that have the permissions to save/delete playlists and would load the loadplaylist.view page in the main pane.
What do you think?