YouTube Leanback was in beta since July this year. "Now, YouTube Leanback moves forward into a new role at the center of the YouTube experience on Google TV, which you'll start seeing in U.S. stores this week. When you view Leanback on Google TV or online, videos based on your subscriptions and viewing history will begin playing immediately, are always presented in full screen and HD (when available), and you can easily browse using just the arrow keys on your keyboard.
If those don't pique your interest, Leanback offers 10 channels, updated daily, featuring popular and interesting videos in genres like Comedy, Entertainment, News, Science & Technology, How To & Style, and more.
You can also watch full-length movies and TV shows rented from youtube.com in the highest quality," informed Google.
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