In the world of the future, where music is as easily accessible as air, the new bread and butter of the music industry is discovery. While services like Turntable.fm center around small social gatherings, and Pandora uses fancy algorithms to predict your tastes, 8tracks asks "Um, hey, what was wrong with how radio worked? Also, do you guys like tablets?" The answers, of course, are "You know, that's a good point," and "Um, YEAH."
8tracks was already a great service centered around user-created playlists. The idea being that people know better than machines do what good music is. Unlike Turntable.fm, though, 8tracks allows all you virtual DJs to create custom playlists that others can then listen to.