Though IMHO http://sugarjs.com/ looks better + have way more github followers.
A monthly $7 (translated from the swedish montly of 49 kronor, not sure what they charge in other countries) isn't that much for the kickass musicservice that is Spotify. What didn't the storage cost ppl when they had their mp3 collections? And the time spent searching and downloading?
Spotify is fast, has a silly amount of music, has good song/playlist sharing functions and new songs start instantly. I wish they had increased the commercials instead of limiting the time for the free accounts.. but still, it doesn't cost that much compared to what you get.
Tried some Grooveshark yesterday when I got this news.. it's not close to as polished as Spotify. Missing songs, you wait for them to start etc.