In preparation for the upcoming Xbox 360 dashboard update, Microsoft has announced that they'll be updating the website Xbox.com over the coming days to implement some of the dashboard's new features before it launches on consoles later this winter.
Users will be able to search the Zune store online and buy and rent movies from their browser, and the social features (one of the ways that Xbox.com is vastly superior to Sony's PlayStation Network website) are becoming much more robust.
The best new feature is the game "beacons" that will soon be available to all Xbox 360 users. When a player wants to find friends to play with online, it's not a matter of dropping a digital beacon that everyone can see suggesting a time and a place to play. You'll be able to go to separate pages for any of your games, and see which of your friends have set becons for those.
As new features go, I think Beacons sound really cool—it's always been difficult to pick times and dates to meet up with friends online, and I anticipate using that feature quite a bit. We'll see how they work once the update is live.
For more detailed information, check out Microsoft's Official update at the Xbox.com blog.