A few months ago, we caught wind of a Facebook and Spotify tie-up which might turn out to be true and may involve other third-party providers.
There are now rumors floating about that Facebook will launch a music service this month (September 2011), but instead of providing an actual marketplace for users to purchase songs, the social networking site will serve as a venue for third-party vendors (i.e. Spotify, Pandora, MOG, etc.) to provide users access to their services.
The same sharing and tracking capabilities are still rumored to be true – you will most likely be able to let your friends know what song you are currently listening to and vice versa. If this does push through, Facebook is expected to announce it on f8 conference on September 22.