It's good. I'm not honestly sure how legal it is, however.
One of the thing that sucks is that it appears to be user submitted without much moderation. There's a lot of repeated songs/albums, and a lot of shorter versions of songs (IE: the album says the song is 16:00 minutes, the Grooveshark version is 10:00).
That said, it's a great alternative to Pandora if you want to choose what you are going to listen to specifically.
