It doesn't appear that Google made an Official YouTube App for Windows Phone. I guess it's really not that surprising, but I wonder if they'll ever change their minds. Until they do, there are some alternatives (listed below):

YouTube (Official Microsoft App)
http://www.windowsphone.com/en-US/ap...0-00237de2db9e

Youtube Pro
http://www.windowsphone.com/en-US/ap...a-c5883c210eee

SuperTube Lite
http://www.windowsphone.com/en-US/ap...2-78e7d1fa76f8

easyTube
http://www.windowsphone.com/en-US/ap...5-d90d53197b99

Youtube Live
http://www.windowsphone.com/en-US/ap...8-a35f2f313d14

Vimeo (Official)
http://www.windowsphone.com/en-US/ap...4-de7a48dd186b

What's your favorite video watching app for windows phone?