Steve Grove at CitizenTube, has a posting about the federal government's use of YouTube:

• The U.S. Government Comes to YouTube (May 21, 2009)

Now, there are dozens of official federal YouTube channels where you can access footage from NASA, the State Department, the FBI, the CDC, and more.

...The U.S. Government channel is located at http://youtube.com/usgovernment, a nifty hub that links off to dozens of federal government channels on YouTube, from the Social Security Administration to the Environmental Protection Agency, with others to be added in the coming months.