Today it was revealed that Facebook will integrate a play button on it's new Timeline Pages instead of customizable apps from places like ReverbNation, BandPages, etc.
In theory, the button will be compatible with any on-demand streaming service such as Spotify, Rdio, MOG or Rhapsody. However, after clicking the button, the music service that the individual uses most will begin playing the song from the artist. Then, like everything else on Facebook, your listening activity will get posted on your Timeline chronology. See below for what it will all look like. [Digital Music News]