It’s supported by ads, you can only play tracks five times, the tracks are streamed (not downloaded) and of modest quality, and (most significantly for me) it only works in the US, but apart from that, the free Napster service — launched today — is the closest thing yet to the vision of a ‘celestial jukebox’. In that vision, people have access to all the music in the world on demand in return for a flat-rate payment.
The free Napster service is ideal for try-before-you-buy auditioning of music (and the recording industry will be pleased that it will help chip away at the argument that people ‘only’ use unlicensed peer-to-peer services for try-before-you-buy purposes).
Napster has also announced the horribly-named Narchive service, which sounds like an attempt to build a proprietary wikipedia for music. At the time of writing, though, the Narchive site just says “beta coming soon”.