It seems a little limited at the minute - online music only, premium (i.e. add free) version only. But it's just a Beta, I think they'll iron those issues out. That the good people at Spotify have even developed a Linux version is enough to make me take notice of them.
I'm not the biggest "social" media convert, the main reason that I'm so interested in services like Spotify & Last.fm is that I have trouble discovering new music and artists that I like. I just don't get to listen to as much radio as I'd like anymore. For me they definitely a lot of the niche that radio used to have carved out.
Anything which helps to point me towards new music that I might not have heard, but might love, gets a big stamp of approval.
