The iPhone (and iPod touch) app is free for the first 100,000 downloads and will then be $3.99. Features include:
- Stream your music over Wi-Fi, EDGE and 3G
- Navigate quickly by artist, album and genre
- Enjoy cover art, artist bios and lyrics
- Connect with up to 30 friends
- Easy setup; no router configuration
It does require installing additional software on your Mac or PC to successfully stream the music.
Unfortunately, it appears that DRM encoded files are not available for playback. This typically includes songs purchased from iTunes. A short video demo is available from the developer: