People <i>like</i> choosing their music -- or at least, the 'anchors' around which a service like Pandora build playlists. Here there's no evidence even of what artists/genres are possible. So the idea people would pay a premium over other rental services -- like Pandora or Napster -- seems farfetched. For your lowest yearly cost ($30*12=$360), someone could own an iPod touch and yearlong "Napster+mobile" subscription.