I recently discovered mpd and found it to be a nice little program. There is a dearth of nice-looking OSX clients, though (besides terminal clients).
hs.socket extension (in master, but not yet in the latest official release), I've created a Hammerspoon frontend that speaks the mpd protocol. With what I have so far, it's already much faster and easier to use than iTunes. I'll link the code on the Hammerspoon wiki once everything is finalized, but an in-progress version is available here.
hs.menubar, I've created a series of menubar items to assist with controlling playback. Hovering over the play/pause icon shows the current track.