Songbird

Awaiting an update to this extension:
http://addons.songbirdnest.com/addon/8

So as of version 1.0.0, Songbird does not respond to external requests to open playlists, nor by dragging and dropping it, nor any easy method.

Go to File » Import a Playlist... to take care of this basic task.

This is also the way to play live music streams in many cases– download the .pls file and import it through the file menu.

Resolution

After a long delay because my poor abused MacBook didn't get restarted for a few months, Mac OS X managed to update iTunes. And the new version, 8, is terrible. There are ugly little arrows everywhere that just send you to the iTunes store for songs you already have.

I don't need a whole separate box to tell me what's playing that hides a third of my playlists. And I certainly don't need an entire idiot sidebar that needs an account at Apple's iTunes store to show it's genius.