It's in beta testing currently, and among other things, that means:
- Only mp3 files. You can't play mp4/aac or other files times from your library yet.
- Only for OS X (Macintosh). They're working on a Windows MixApp client.
If you're on a Mac, come join my MixApp group!
You can listen to some of the rooms I've started up there and filled up with music (freefall, Ecto, 80's, Afropop Worldwide, Southern Rail, Finland, Massachusetts Music) or add your music to them or make a new room or two.