The hub for all of your Windows 8 related Xbox gaming received an update today and should be available immediately.
According to the release notes the update includes the below listed improvements/functionality:
- A new home panel that shows you information about your recent game activity, messages, achievements, and friends
- Letting you view and browse screenshots for games
- Letting you see and send text messages to friends
- Improvements to general browsing of games and game extras and app layout
- Additional minor fixes and improvements
To be honest these are pretty detailed release notes in comparison to many who just use that last line and publish. We need this more often in all app updates in the Windows Store.