I got a chance to use it today. You can browse by album, artist or genre and listen to 30 second clips of any song to see if you like it.

Individual songs are indeed $0.99 apiece but an entire album is $9.90. (Expect prices to go down and available tunes to go up as the service works out the kinks.)

The files are in AAC format, not MP3 and are keyed to your Apple Music login and password which you can set on up to three separate computers as mentioned below.

The service is integrated into iTunes, where you can browse, sample, purchase and download the music. Songs purchased can reside on up to three computers simultaneously and you can sync them up with as many iPods as you want. The music can be burned to CDs but any given playlist can only be burned ten times. (You just have to manually rearrange the songs to reset the burn count.)

As an added bonus, they finally put Rendezvous support into iTunes.

The new software required is iTunes 4, Quicktime 6.2 and iPod updater 1.3. (all are free downloads)

The downside: it's currently US only as international licensing gets ironed out and it's currently Mac-only. (I don't consider that last a downside myself, but some do.)

Windows support is supposed to be available by the end of the year.

It's pretty cool and easy to use. I snooped around this afternoon and found a John Prine album ('Sweet Revenge) that I hadn't seen in a store in years. In fact, the last time I saw it was pre-CD. I like the fact that there's no monthly fee, that you can sample music easily and that you can buy individual tracks instead of digging through thirteen tracks of junk for the two songs you actually like when you buy a CD at the store. In addition, there are 'Staff Recommendations' and ala Amazon, 'others who bought this music also bought xxxxx'.

One possible caveat: This thing is so easy and convenient to use that it could bring new meaning to the term 'impulse purchasing'. It's about as close to a frictionless shopping experience as I've seen yet.

Word is that the 'Big 5' have only signed a one year commitment so they can see how it works out.

As proofs-of-concepts go, I think it's a winner.

That being said, I'd like Apple to publish some ongoing stats on how the service is doing.