GDR2 update for Windows Phone 8 is live.

I am downloading the update on my HTC 8X as write this after getting the notification early this morning. My phone is unlocked and if you haven't got it yet, just go to Settings > phone update and tap the check for updates button. Don't freak out if no update is available yet; Be patient and try again later. Until then, check out the change log:

Xbox Music. It's now easier to select, download, and pin music. Plus, music fans will see more accurate metadata (such as song and album information) and many other performance improvements.

FM radio. Listen to FM radio right from the Music+Videos hub. (Not available for all phones.)

Data Sense. Stay on top of your phone's data usage with Data Sense. You can set a limit based on your data plan, or just keep track of which apps use the most data. (Not all mobile operators offer Data Sense.)

Skype. Voice over Internet Protocol (VoIP) apps like Lync and Skype now feature improved stability and performance.

Internet Explorer. Your web browsing experience is now better than ever with improved HTML 5 audio playback.

Camera. Set your favorite Lens so it opens automatically when you press the camera button. (Not available for all phones.)

Other improvements. Includes many other improvements to Windows Phone.

Source: Windows Phone 8 Update History