Jon Stewart's interview with CNBC's Jim Cramer (you can view it in its entirety here, here, and here) is really worth viewing. I'm not sure whether it's Stewart at his most effective or most annoying. Perhaps both.
It's actually very similar to his appearance on Crossfire back in 2004. In both interviews, you have an admittedly fake journalist lecturing slightly more real journalists on their responsibilities. Stewart proceeds from an almost unassailable position. His show is an entertainment show, and he doesn't claim it to be anything beyond that. Then he criticizes journalists for resorting to entertainment to sell their shows. With Crossfire, he told Carlson and Begala that they posit themselves as a debate show, but they're really providing cheap entertainment that just serves the politicians. Cramer, Stewart alleges, actually understands finance but dumbs it down with cheap stunts and convinces people to buy stocks they shouldn't be buying.
Stewart is undoubtedly right in his criticism. Of course, imagine what shows like Crossfire and Mad Money would look like if Stewart ran them. They would invite politicians and CEOs on the show and criticize them heavily when they dissembled and try to explain to viewers when they're being lied to. This would certainly be useful, except that no one would go on the show. With no one on the show, no one would watch it.
It was no accident that the only one telling King Lear the truth was the fool.