Have not tried it yet.

http://www.washingtonpost.com/business/technology/youtube-releases-own-iphone-app-as-apple-prepares-to-drop-video-service-as-built-in-program/2012/09/11/6391b7d2-fbe2-11e1-98c6-ec0a0a93f8eb_story.html?tid=pm_business_pop

(from comments)

Would be nice if the Post offered a link to the App. Here it is:

http://itunes.apple.com/us/app/youtube/id544007664?mt=8