If you managed to get yourself on the Xbox Live preview program for the new Xbox 360 Dashboard, you can add YouTube videos to that list of platforms. Beta participants should now be able to download the app from the console’s new Apps Marketplace and you will find all different personalized features you would normally expect from YouTube. From adding your favourites to creating your playlists.
There’s no word if it’s been launched everywhere as of yet, but it’s promised for later in December. So turn on your Xbox 360 console and see if it’s available, if not, you’re going to have to wait for it to be added eventually.