The clue is kind of in the title really, but if further clarification is needed, the Xbox One will launch with its YouTube app available from day one.
The YouTube app will allow Xbox One owners to view videos in 1080p and can be controlled using voice and gesture commands via Kinect.
Sadly, the Snap functionality we saw at E3 will not be ready at launch but Microsoft promise that the ability to view YouTube videos whilst using the Xbox for another function will come along shortly.
The YouTube app will be available to all territories (except for Australia, New Zealand and Ireland which will take ‘a few days’) from launch.
Presumably best to avoid those PS4 Call of Duty: Ghosts videos though.