Steve Grove of Youtube writes (youtube.com/blog?entry=20h2yiH79Tc):

President Obama is taking your questions this Wednesday in a special online health care town hall event. With health care at the top of the President's agenda, he is opening up the White House to questions via YouTube... He'll answer some of the most popular questions during the event, which we'll stream live from the White House YouTube channel.

In a word, this is a sham. And, it's similar to all the other shams that Youtube, CNN, Obama, and others have conducted for the past couple of years; see the popular voting systems summary for the background. Basically, the president of the U.S. is trying to fool people, and a private company is helping. In the current case it's even more obvious: they'll only choose "some" of the questions, and how exactly they're determining popularity isn't spelled out. In brief, Youtube is going to choose videos that are basically just set-ups from those who aren't experts in this field.

There are two things to do here (but that won't be done): do an end-around such filtering by trying to ask Obama and other politicians questions in person (see question authority), and for an actual expert to submit a very valid but adversarial question that Obama would have trouble with. If that question is selected, then it might make Obama look bad. If that question is not selected (the far more likely option), then the fact that Youtube didn't choose it can be used to make Youtube look bad.

UPDATE: The things I do for you! I just spot-checked about 15 of the 300 or so videos, and all are as bad as we've come to expect. Almost all boil down to one simple phrase: "when do I get *my* pony?" While some of those people may have valid concerns, the "questions" they're asking will simply give Obama an entree to a stock response. They're doing a public disservice by simply acting as foils for Obama. If they really wanted to do a public service, they would find an expert to ask the questions about their concerns instead of simply posting worthless vanity videos. Just because you have a case doesn't mean you should do your own lawyering.

UPDATE 2: I added my own video.