A popular app for Windows Phone is now available for Windows 8 and Windows RT! Metrotube for Windows 8 is a beautifully designed third-party YouTube app, and is available in "public preview" form for download right now!
For those that don't know, Metrotube was created by Lazyworm Applications. These developers are the same guys who created Metrotube for Windows Phone and Tweetro+ for Windows 8. Metrotube for Windows 8 is an excellent app that lets you stream YouTube videos in high quality, HD, and Full HD.
Metrotube is pretty much a fully functional Youtube app with all the features you enjoy on the popular video website, such as video searching, video sharing, subscriptions, favorites, and the ability to watch videos later. Metrotube even features a Live Tile!
Lazyworm Applications is working on adding more cool features to Metrotube, including playlist support, pre-loading of video content, and secondary pinning.
If you are a frequent YouTuber, go grab this app! Its free!