Mobile radio content feeds

I know that a number of Nokias (and others) have a built in FM transmitter, but there are many popular handsets that dont. Radio is a ubiquitous music experience that is understood and appreciated by the masses. MSpots approach to wrapping this in to the device mediaplayer for a monthly subscription is smooth. What excites me are the future possibilities of this; podcasts, video streams, purchased music, audio books, live user-generated radio broadcast feeds etc...