Spotify has launched in the U.S.

The service has signed deals with the four major music labels in the country, reported All Things Digital, finally giving the green light to launch.

Spotify is a streaming music service that lets users create playlists and share them with their friends.

For now, the free service is by invitation only, but it is expected to open up in the coming weeks. Paid plans are available immediately.

The U.S. launch has three plans, much like the plans available in Europe. The free, ad-supported service gives users access to a number of tracks on Spotify through the Web, lets users organize and jam to their own music and gives access to Spotify Social. According to Spotify spokeswoman Alison Bonny, the free service that launched today has no time limits as part of an introductory offer, but Spotify will eventually cap users to 20 hours per month, the same model it has in Europe

Spotify Social is the realization of the site’s rumored Facebook integration, and it lets you post playlists to which your friends can subscribe.

You can also import your Facebook friends into your Spotify profile and share tracks by using the service’s Inbox. The inbox lets you know who has shared a particular song with you and when they sent it.

For $4.99 per month, users also get to ditch ads and get access to the Spotify radio mode. For $9.99 per month, you get mobile access to your playlists, access to offline modes for your desktop and mobile device and access to exclusive content.

The service made waves in April when it made changes to free accounts in Europe, halving the time that users can listen to music and limiting the amount of times users can listen to a single track.

I’ll be playing around with the service today and posting my first impressions later. What would you like to know about Spotify?

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