Microsoft Starting To Roll Out Xbox Live Update Preview aka Social Integration and Full HD Streaming

If you registered early for the Xbox 360's social integration then you should note have the Xbox Live Update Preview. When you log-on to Xbox Live it tells you to update. If you didn't get an invite yet, then be patient because Microsoft will be rolling out more invites as the days go by. This update will give you Facebook / Twitter / Last.fm integration and, even better, 1080p instant-on streaming.

[Engadget]