They claim they'll be able to make better music recommendations (curated by humans rather than algorithms) and on-the-fly playlists than Spotify.
From http://blog.beatsmusic.com:
We tried to remember a time a robot found us magic but all we could find were the times the robot made us laugh: “You like Pantera? Have you heard of Black Sabbath?” “You like Mumford and Sons? Here’s another song with banjos!”
Just tell Beats Music where you are, what you feel like doing, who you’re with, and what kind of music you’re looking to hear and we’ll take care of the rest by delivering you an endless playlist for your context, be it real or imaginary.