The new version of the service, which does not allow users to upload music from their hard drives, instead relies on bands to submit their own tracks for listeners to play on Muxtape--and Muxtape only.
There are a dozen bands to start with, all of which have been hand-picked by the service's creators. Bands that are interested in getting their music onto the service will be able to sign up once the service relaunches in earnest. According to Wired, artists will then be able to sell their tracks from places like Amazon MP3 and iTunes by paying Muxtape a fee. There has been, however no mention of whether that fee will be per referral or on a subscription basis.
Until the official relaunch, users who were previously registered with the service will find that their log-in credentials no longer work. Likewise, you're unable to assemble any of the tracks into a custom playlist--one of the highlights of using the service.
(via Daring Fireball)