Officially as of the 8th April Xbox One owners can now upload gameplay clips captured using Microsoft's Game DVR functionality directly to YouTube.
Quote by GameSpot
You will be able to click a button inside the YouTube app to share clips to your YouTube channel. By comparison, Sony's PlayStation 4 does not offer any YouTube app whatsoever, though owners of that system can share clips to their profiles or to Facebook using the system's "Share" functionality. The PlayStation 3 and PlayStation Vita currently have dedicated YouTube apps.
The updated YouTube app will also let you watch videos in Snap Mode, add new videos to your Pins, earn Media achievements, and add your favorite YouTube channels to the OneGuide.