Anecdotally, most of my family and friends are casual listeners who prefer Pandora and traditional radio to decide for them what to hear next.

Spotify and Beats Music are for big music fans like myself who want to hear a specific song or playlist from their favorites. But there's a much smaller market for big music fans. If Beats can make a play for the Pandora/iTunes Radio audience they have a chance. Otherwise they have to prove they are better than Spotify, Rdio, Rhapsody, etc. for hardcore listeners.