As long rumoured, Facebook has announced that it is working with Spotify to offer music through the social network. But, as you'll read, you'll still need to have the Spotify app installed for it to work.
The move was announced at Facebook's F8 confrerence today Mark Zuckerberg announced "two of the most exciting things we've ever done". The first was Timeline, a more visual way to explore Facebook.
Facebook has announced a number of changes to the site over the last few weeks, but the link up with Spotify is a big step for Zuckerberg's army.
The first hint that a link-up between Facebook and Spotify washappening came in August 2010, when a revamp of the service offered deep Facebook integration.And when Spotify launched in the US it seemed like it was only a matter of time.
Here's what you need to know about the announcement:
1. Facebook now has a Music app
The service isn't offered through a specific Spotify app - instead you'll now have a Music app in your Facebook profile sidebar. Spotify is a featured service within this. Spotify calls this page your Music Dashboard, though we're not sure if that's an official name or not.
Speaking about the Spotify app, Daniel Ek from Spotify said: "Finding new music is always difficult and that is why we created Spotify.
"We have spent the last few years building a service where you can find music. Add this to Facebook's 800 million users and this will light up the world."
2. It's a new type of app
Music is the first type of a new 'open' app from Facebook (called Open Graph) - enabling any company to create an app that allows social interaction.
Mark Zuckerberg said about the apps: "The open graph is a completely new class of social apps to discover new things with your friends."
Other names on board with these new apps are The Guardian, The Independent, Netflix (not UK) as well as Nike Plus.
Other music services to have signed up include Deezer and SoundCloud.
3. You can play music directly from your Facebook page...
You can click a play button from your Facebook newsfeed or Music Dashboard and the music will start. Though there's a caveat...
4. ...but you'll need to have Spotify open
One thing that's played down is that you'll need to have Spotify open to play music. If it's not open, you'll see this message and Facebook will try and open it.
And the Music you're recommended won't necessarily be on Spotify - we've already been recommended a Feeder album that's not on the service.
Now, it's worth pointing out that this won't give you a total music experience through Facebook. It's the social experience that you're sharing, so you can listen to tracks your friends are but you can't search for just any old track through the Facebook interface. Think of it as another way to discover music with Spotify rather than a new interface to play music through.
Here's the permission screen you'll see from within Spotify.
5. Spotify on Facebook will be free
"We knew that the service had to be free to draw people away from piracy," continued Ek - but of course, you'll still need to have a functioning Spotify app to use it.
"Helping them to listen to even more music. To do that, we also knew that the service would have to be inherently social. There couldn't be a better place to do this than Facebook.
"This integration with Facebook will help everyone to discover more free music than ever before. Thanks to our unrivalled, truly free service, users can just hit play to enjoy the music, no hassle, no gimmicks; month after month after month."
4. You'll see what your friends are listening to
You'll now start seeing new music posts and play buttons in your newsfeed, while your friends will be able to see what you're listening to - providing you give Facebook permission of course.
7. Spotify reckons that more people will buy music as a result
"We know that Spotify's users who connect to Facebook listen to more music on a weekly basis," continues Ek. They listen to a wider variety of music – in fact we have more than 400 million playlists created in Spotify now. Because these users are more social, they're more engaged. Because they're more engaged, they're more than twice as likely to pay for music
"Social discovery on Facebook means that we're bringing people back to paying for music again. And that's how the brilliant artists who create this music can continue creating it for us to enjoy."
8. Facebook will fill in the social gaps that Spotify lacks
Since its launch, Spotify has enabled you to scrobble to Last.fm to keep track of your most listened to artists and tracks. You can still do this, of course, but now your Facebook Timeline will populate with your listens, as well as your top albums, playlists and artists. And it will also provide the recommendation tech that Spotify has so needed.
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Dan (Twitter, Google+) is TechRadar's Former Deputy Editor and is now in charge at our sister site T3.com. Covering all things computing, internet and mobile he's a seasoned regular at major tech shows such as CES, IFA and Mobile World Congress. Dan has also been a tech expert for many outlets including BBC Radio 4, 5Live and the World Service, The Sun and ITV News.