For the artists, Spotify is one of the perfect platforms where you can share your talent with the world and can get millions of followers. However, it will not be very easy for every artist to get a large number of followers. Therefore, you can get services for Spotify playlist promotion at the platform of Spotistar.
Yes, I do. Pretty useful for finding new music to listen to. Althought the ads on the free version can be annoying.
Yeh, its good. I prefer last.fm (on xbox) its much better.
Grooveshark is pretty good too. Worth checking out.