[JAVagueArgument]

It is only hitting the U.S. now because, like many companies, they built a following in a smaller area first. They then used that to get record companies hooked as a small start up. The more they grew the more back catalogues and even indie artists got on board with them.

So now they have a proven platform, architecture and refined client and importantly a tested price model (like I said it has changed frequently to find the right form). So they felt ready to move to the US where there is a much larger audience. I believe they also secured a big investment to help too.

Add into that, the EU and UK do not have software patents, so it is much easier to make software over here than in the US. So of course as soon as Spotify go to the US they are under litigation from the software patent trolls.

As for unlimited music streaming, it used to be Naptsters legal business model a few years ago, but the internet just wasn't fast enough back then and they were blocked as there was only iPod and it had no apps.

Oh and what separates it from Grooveshark, Pandora or We7 you ask? It is their software client, it caches music, for fast access and less streaming, it can be used offline, and they have mobile versions for the $10 subs. HTH