Those in the know have been waiting for new music service Spotify, which went live to a small group of invitees in early December, to finally became freely available to everyone. And yesterday the shout went out to UK web users “come and get it”.

Spotify is an ad-supported streaming music service that lets you listen to as much music as you want, for absolutely no cost as long as you don’t mind hearing the occasional advert. Or, if you’d rather, you can pay a small subscription fee (£9.99 per month) and get the whole service ad-free.

And people are getting very excited about Spotify. I attended Marketing Week’s Interactive Summit two weeks ago, and not only was Rob Wells Universal Music’s Head Of Digital raving about it, so were a good number of the delegates who had already managed to get an invite to use the service. And the plaudits keep on coming…

Top technology site cnet claims that “Spotify is quite simply, in our opinion, the best thing to happen to music since MP3s. All we need now is a mobile phone app for it, and we’re golden.”

While Flo Heiss, Creative Partner at top digital agency Dare was excited enough to claim Amazing. This is where it’s going to go with music. Music will just be there. Whenever, wherever, whatever. No downloading necessary. Just listen.

So why is Spotify so good, after all we’ve seen both subscription services (Napster) and Ad-Funded music services before (WE7)?

Well it may be something to do with the simplicity of use, the quality of the streaming, and the seemingly bottomless collection of music to chose from (all the major labels are on-board, and many of the indies, with the catalogue growing at a fast rate). And as yet I’ve only heard the very occasional advert.

So why would you want to stop using the excellent iTunes service, or get rid of your emusic subscription, and possibly even pay for Spotify? Well I don’t think for real music heads that time is quite here yet. After all the music is not portable, so I can’t use it on the move. However, with ubiquitious mobile internet just around the corner and data charges decreasing, I’d expect to have Spotify on my mobile device in the very near future.

However as blogger Henrik Ahlen points out this sort of service has some real advantages over what is currently available. He gives four reasons why he thinks services like Spotify are the future:

1. I don’t want to own files or CDs, I want to listen to my favorite music and find new music easily.
2. I don’t want to fill up my hard drive with Gigabytes of media files that can vanish in a hard drive crash.
3. I want to listen to my music library on multiple computers and on my iPhone mobile.
4. I want to be able to share my music easily with friends and family.

And Spotify is either delivering all these services now, or will be in the very near future. For someone like me who has been buying and collecting music for nearly 40 years, this seems a rather odd service to get excited about, as after all you own nothing. But actually all I’ve ever wanted is access to all the great music that I can listen to. And it gets over the problem of having a sudden desire to hear an old song again, without having to hunt around for it or buy it anew, to find you only wanted to listen to it a few times for memory’s sake. Only a handful of the 9,500 tracks on my hard drive have been listened to more than a 10 times, I listen to lots of different music, not the same handful records all the time. I still want to hear lots of old music, new music, and even blue music. What I want is to borrow lots of music at a reasonable price, and a service like Spotify offers all that!

And before you go on about it not being perfect (the home page looks awful, not sure about the recommendations, no user generated reviews, no info on individual releases) Spotify is still pretty new out of the box, so I’d be prepared to give it some time to develop. Anyone who used last.fm back in the day will testify that it wasn’t perfect. This is a really neat service that lots and lots of music fans will love. It may not convince all the nerds, but it’s already proved a great way to listen to the stuff I can’t get on emusic.

The business advantage for the music industry of this sort of service is that it could help kill off file sharing (why would you want to use dodgy file-sharing services when you can have this?) and provide a legitimate revenue stream for both artists and record labels. Rob Wells was bullish enough to say he thinks in the next 5 years ‘access’ based services like Spotify will ensure that record labels will be more profitable than they have ever been. You can expect to see a lot more services like this appearing this year, with many of the broadband suppliers, including the likes of Sky come into the market.

As you can probably tell I’m sold on Spotify, if you want to find out what all the fuss is about click here.