If you have 15 spare minutes, here is an interview:
Sheldon's dialogue with Brian about the very same issue. Just kidding, a big fan.
Incidentally, my Czech translation of The Elegant Universe is getting ready for the imminent 2nd edition after 12 years.
Brian reveals that the definition of the "world" in the World Science Festival has been extended from "New York" to "New York and Amsterdam" which is quite good.
Also, he seems to be working on extensive video lectures using some of the newest media technology that should provide the smart high school students and other interested laymen and amateur physicists with some explanations of physics that go deeper to the technical content of physics than garden variety popular accounts usually manage to. That could be pretty interesting.
Of course, they also discuss string theory and similar topics. Brian Greene mentions that maths is surely important for physics but one can't a priori know "which maths" and he says that he would be shocked if the ideas and maths of string theory don't apply to the Universe around us but he would love to know the answer whatever it is. I may subscribe to both assertions.