For at least fifty years of the 20th century, the relationship between music and radio airplay was fairly well understood. Record executives knew that if they wanted a hit record, they needed that song to get played on the radio, preferably as many times as possible. In fact, until 2000, radio airplay was essentially a prerequisite to selling significant amounts of recorded music.
Clearly, radio airplay is still critical – especially for genres like pop, country and urban/R&B – but in recent years both radio and the mechanisms for selling music have been upended. Traditional commercial radio, with its limited playlists and regional reach, has been challenged by new forms of radio: webcast versions of existing stations (including WFMU), pureplay webcast stations like Soma-FM or Pandora, and Sirius XM satellite radio. Then there are the interactive services like Spotify, Rhapsody, Last.fm, and Rdio, many of which mimic radio through playlist options or pre-programmed channels. And there’s YouTube, now considered one of the most widely used sources of music discovery in the world.[…]