MySpace Music is scheduled to launch tonight. It’s an ad-supported free on-demand streaming service, with Amazon integrated as its download store, and some cool angles on sharing and discovery (including share-able playlists). MySpace has an interesting vision of artist stores — where you could buy ring tones, songs, merchandise, concert tickets, etc. but that’s still being fleshed out.

Since MySpace Music is a joint venture with all the big four labels, it will have a good catalog beefed up by the Orchard’s strength with indies. MySpace has a good track record in building a platform for indie artists, and delivers the audiences. And MySpace has already proven itself as a leading online site for music info, discovery, and listening.

Editors will program the front page and do some curating and promoting of celebrity and MySpace user playlists — MySpace hopes to be a path to amateur DJ stardom. Community curation and recommendation should play a part, too. JupiterResearch teen surveys show that 51% of the best teen music fans use social networks to find out about entertainment, and 35% use them to listen to music.

Finally, MySpace has a big ad sales force and is pushing the envelope on social marketing sponsorships, and starting to on targeting. It’s announcing with four premiere sponsors: McDonald’s, Toyota, State Farm and Sony Pictures.

It won’t have:
– For-pay on-demand subscriptions
– A radio-like offering
– Merchandise sales and ticketing (to come)
– Free downloads that run on your iPod (you can buy them from Amazon)
– Audio ads (I know, I know, they s*ck, but they’re probably necessary)
– A graceful way for indies or unsigned artists to get paid (they have to work through Amazon or the Orchard or someone else)

Jupiter has been saying for years that one of the promises of online music is the ability to blend discovery, listening, and retail experiences the way no other medium can. That’s a good vision, right? Too bad there hasn’t been any proven demand for it. Perhaps MySpace will tap that hidden demand — they’re in a very good position to do so. Online discovery, for example, can and should tap word-of-mouth recommendations from friends and influentials (rather than broadcast). That’s a natural for social networks, and MySpace will try to encourage playlist-sharing (so far not used by many), as it has successfully encouraged song-embedding on personal pages.

MySpace will make its money on ads — affiliate fees for downloads will be gravy, if they’re lucky. MySpace Music isn’t quite as rich an offering as Rhapsody or Napster (yet?) though it may appeal to aficionado audiences as well as younger fans. We’re more bullish on ad-supported services reaching mass markets, but still see a role for premium products for the most serious fans.

Billboard has the best story
TechCrunch has screenshots