Hello !
It would be awesome if Subsonic could be a MPD client. It's the only feature that is missing from Ampache (or Jinzora)
Currently I have several PCs in my house, when I want some music I go on subsonic and play it via the flash player or playlist.
If subsonic was able to control a remote MPD server, I would be able to start a playlist in my kitchen from my living room (for example).
It would work just like the jukebox mode but instead of playing on the subsonic-host soundcard it would stream to one (or maybe several at a time ?) configured local or remote MPD server.
I don't have any idea how hard it would be to implement such thing.
Here are some docs:
Java library for MPD: http://www.thejavashop.net/javampd/
General MPD prtocol documentation: http://www.musicpd.org/doc/protocol/