The New York Times' Frank Rich on what makes The Daily Show with Jon Stewart so good:

"The heart of his show is the faux 'news' broadcast that opens it each night. A typical segment consists of byplay between Mr. Stewart, who serves as anchor, and Stephen Colbert, the self-important, terminally patronizing 'senior correspondent' who is reporting from the 'scene' (a bogus backdrop) of whatever story is at hand. The staff of 'The Daily Show' finds laughs by taking the facts of a news story more seriously than real TV journalists sometimes do. Right through the war, for instance, most TV reporters mindlessly parroted the Pentagon speak of 'coalition forces' without qualification, as if the dozens of allies touted by the White House were providing troops to the American war effort. On 'The Daily Show,' by contrast, "Coalition of the Piddling" has from the start been a continuing logo for reports on coalition 'partners' like Morocco, whose contribution to United States forces was 2,000 monkeys enlisted to set off land mines. (That's not satire; 'The Daily Show' picked up the story from The Washington Post.)

"Mr. Stewart and company were on top of 'The Halliburton Connection' (as another segment logo has it) well before much of the media spoke up loudly about the nexus between Dick Cheney's former employer and lucrative government wartime contracts. When Mr. Stewart asked Mr. Colbert for his take on whether Saddam was dead or alive, the correspondent answered, 'One thing is certain: If Saddam is dead, it greatly reduces his ability to control Iraq.' But wouldn't his death end his control entirely? asked Mr. Stewart. Not necessarily, argued Mr. Colbert: 'When this man appears in public no one is sure it's actually him, and yet he's held an iron grip on power since 1979 — 24 years of brutal dictatorship, all while only maybe existing. The point is we can kill Saddam Hussein but we won't win the war until we kill the idea of Saddam Hussein. So what we need to do is develop bombs that kill ideas.'
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"But the war itself increasingly became the subject, and the jokes about President Bush depart from the late-nite clichés. The Bush on 'Saturday Night Live' may still be frat-boy simple, wishing that 'Shock and Awe' had been named 'Tango & Cash,' but 'The Daily Show' sees a slicker operator. After the president told the Iraqis in a subtitled TV address that they were 'a good and gifted people' who 'deserve better than tyranny and corruption and torture chambers,' Mr. Stewart cited it as proof that "condescension knows no borders." Nor is the show taking at face value the White House's professed devotion to postwar Iraq. 'We won,' said Mr. Colbert in his 'report' from Baghdad 10 days ago. 'Rebuilding is for losers. Time to party! Then it's off to Syria for the next invasion.'
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"'It's so interesting to me that people talk about late-night comedy being cynical,' Mr. Stewart says. 'What's more cynical than forming an ideological news network like Fox and calling it `fair and balanced'? What we do, I almost think, is adorable in its idealism. It's quaint.' He's not wrong. During this war, the notion of exercising cant-free speech on an American TV network, even a basic cable network, has proved to be idealistic, quaint and too often restricted to Comedy Central at 11 o'clock."