Today, with music services on Facebook, there’s a new way to listen with friends. This feature lets you listen along with any of your friends who are currently listening to music. You can also listen together in a group while one of your friends plays DJ. 
You can listen to the same song, at the exact same time—so when your favorite vocal part comes in you can experience it together, just like when you’re jamming out at a performance or dance club.
The idea is that while you are checking the latest news from your favourite musician/band you can just click up there and Spotify, or one of the Facebook supported music apps, will start playing music from that band/artist, frictionlessly. In the US some of the music streaming apps are; Rdio, MOGand Slacker Radio. 
Facebook says “The new button will give music fans an easy way to listen to songs through their favourite services, such as Spotify and MOG, directly from Facebook Pages. After clicking the button, the music service the person uses most frequently will begin playing songs from that artist. Because the music services are timeline apps, listening activity will be posted to timeline as it happens.”
Clicking on the Listen button opened a dialogue box asking me if I wanted to open Deezer or Spotify. Then a new browser tab opened if Deezer was chosen, or my Spotify app on the computer opened if that was chosen, music started playing. Going to a different Facebook band/artist page and pressing Listen then failed with Deezer, in this instance, because they don’t have any David Bowie tracks… So I closed the Deezer tab, pressed the Listen button again and chose Spotify, which had a lot better selection. There doesn’t seem to be an option to avoid the Facebook app and dialogue box and just always use Spotify. As such this Deezer is going to get deleted right now from my Facebook apps.
How It Works
Look for the music note in the chat sidebar to see which of your friends are listening to music. To listen with a friend, hover over their name, and click the Listen With button. The music will play through the service your friend is using. When a new song plays, you’ll come along for the ride, discovering new music while your friend DJs for you.
Spotify music player shares/likes on my Facebook news page play right there; no new open tabs etc, and I was expecting more of that type of embedded streaming functionality from this Listen button. I’ll just continue to listen to my WMP which already has all my favourite musicians playlists in; my musical likes in Facebook are of my favourite musicians so it’s pretty much duplicate content to what I already own. For discovering new music I think searching a band/artist name or even genre that has caught your interest works better on YouTube.
