Facebook today announced the “Listen With” button, which will allow users to listen to the same song simultaneously. The feature will roll out over the next few weeks, starting with Spotify, then adding other Open Graph music services.

From the chat sidebar, users can see which friends are currently listening to music. Clicking “Listen With” will open the music player and begin the song at the same point the person’s friend is now at. It also launches a new chat window so friends can comment about the songs they share. Listening to music with friends in this way will publish a News Feed story about the activity, according to Techcrunch. Facebook has never shared chat activity with a users’ friends before, but this is similar to how Google+ shares stories when users video chat with each other.

One problem with Listen With is that users will have to use the same app. If someone is using Spotify, friends can’t click to listen to the song in Rdio. According to AppData, Spotify is by far the leading Open Graph music player with 4.6 million daily active users to MOG’s 10,000 DAU and  Rdio’s 7,000 DAU. The Listen With feature is likely to only increase this disparity and make Spotify the defacto music service of Facebook.

The new feature is similar to Turntable.fm and Google+ Hangouts, which facilitate synchronous listening or viewing experiences. Turntable.fm has users choose avatars and join virtual rooms where people take turns playing DJ. The service is more about discovering music through strangers with similar tastes than sharing with friends. Google+ lets users join video chats called “Hangouts” and share YouTube videos that friends can watch at the same time.

If Listen With takes off, Facebook could add a similar option for video streaming services. We could also imagine Listen With activity becoming an option for Sponsored Stories in the future. Promoting a shared listening experience could be quite meaningful for artists.

If Facebook ever made Chat available between users and subscribers, rather than just between friends, Listen With could be an interesting way for fans and artists to interact. Turntable.fm has seen activity spike when popular artists like Diplo, Sir Mix-a-Lot and Talib Kweli joined rooms. However, since opening Chat to users with asynchronous relationships might be tricky for Facebook, celebrity partnerships could end up being Turntable.fm’s way to survive after the launch of Listen With.