- add plugin support
  - make juk, xmms support plugins
- MPD support
- support players in Kelly's spreadsheet (see panel-devel list)
- VLC pre-DBus support?  See /usr/include/vlc/mediacontrol.h
- find a player that exports album artwork, and test
- separate the watchers and plugin bits into a library?
- unify the watchers?
- finish service support
