The Colbert Factor? The O'Reilly Report?

So Colbert did a guest spot on O'Reilly, and O'Reilly did a guest spot on Colbert, and they wore nearly-identical pin-striped suits, and world didn't end. Nor was the world treated to something uproariously funny. Last night was curious-funny, and that was probably enough.

The "Colbert Report" crew was absolutely giddy; they had packed their set with props, from a "Bill O'Reilly Advent Calendar" (with Colbert as the Virgin Mary, and O'Reilly as Baby Jesus) to a portrait of O'Reilly in a gilded frame. "You're not high," O'Reilly told his studio audience. "Bill O' Reilly's actually here tonight...OK, you might also be high."

O'Reilly, meanwhile, seemed to view the experience as an anthropological experiment. He tried his hand at a Colbertesque interview; his first question was, "Colbert. That's a French name, is it not?," and his fourth or fifth was "Don't you owe me an enormous amount of money?" He played along gamely as Colbert played him. And when the segment was through, he convened a panel of media critics to explain what this Colbert phenomenon was all about.

It was striking, actually: Bernard Goldberg, perennial critic of the "liberal media," waxed nostalgic about the days of Lucille Ball, when comedians merely laughed about themselves. He's right that Colbert and Jon Stewart are "wise guys," experts at mockery. (Though parody has been around a lot longer than Lucille Ball.) But what makes O'Reilly so fascinating -- and what Colbert has managed to nail so completely -- is the fact that he seems, on TV at least, to be the opposite of self-deprecating. At the end of last night's "Factor," he read an e-mail from a viewer: "Bill, do you think you have ever been wrong?"

"I know I've been wrong, Steve. I read your letter," O'Reilly said. He was smirking at the time, but only partly because he was kidding. The other part of him was proud.

He repeated the joke again on "The Colbert Report," and in terms of sheer timing, it may have been the best line of the night.

"We may make mistakes," Colbert said, O'Reilly-like, "but we never admit mistakes."

"We should admit them," O'Reilly replied. "This was a huge mistake, me coming on here."

The audience howled, in deep appreciation.