There are a lot of people who I think could put valuable input on all of the questions on bigthink. Yeah, there are professors, but why not branch out to others who are concerned? I'd be willing to bet that the members of Green Day and Linkin Park would be happy to speak out. In fact, I'd say a lot of entertainers could keep things interesting, or at least sprinkle some relief into all of these serious topics. Even comedians like Demetri Martin and Lewis Black, maybe even Dane Cook could add some comic relief, while still providing honest depth in their answers.
So, apart from who I've already stated: Stephen Colbert, Jon Stewart, Ellen DeGeneres, Dr. Michael Eric Dyson, Sean Penn, Mahmoud Ahmadinejad, various world leaders, and Lex Luthor.