Google's Matt Cutts has posted hundreds of videos on the Google Webmaster Help YouTube channel. The videos consistently get better, more details and useful.
Matt Cutts basically answers questions submitted by SEOs and Webmasters. But how do you get Matt to answer your question on video? It is a good question and it was asked at a Google Webmaster Help thread.
Every now and then, Matt will post on his blog that he is accepting questions. I believe the last time he announced it was in May 2010 and you basically had to submit your questions on a Google Moderator page. Typically the questions with the most votes were answered, plus some questions Matt found interesting.
Matt, how about a video on how you pick up the questions you will be answering?
I got lucky and Matt answered one of my questions:
Forum discussion at Google Webmaster Help.