They have a warmup comedian -
Paul Mecurio - that starts "warming up" the audience before Jon Stewart himself appears. Then comes Q&A with Jon Stewart. Either all the people asking questions were plants, or the same questions have all been asked a gazillion times before, or Jon Stewart is FAST. He had the perfect smart-ass answer for all the stupid questions.
One interesting thing for me was ... I was sitting right behind Chuck, the director/tech guy/whatever you would call it, who controls the feed for Jon's teleprompter. What Jon was saying was sort of what the teleprompter said .. but really only very sort of. He fucked up the second act completely and had to restart, and his second take was completely different from his first take.