It's always good television when Jon Stewart and Bill O'Reilly yuk it up, and last night was no exception. Stewart surfaced on The Factor last night as part of promotional push for The Daily Show's new book Earth: A Visitor's Guide to the Human Race. O'Reilly, who also has a book coming out, thinks Stewart's has too many pages! "Okay Stewart, why do I have to get a sprained wrist when I buy your book?" O'Reilly asks. "Because I put effort into my books!" Stewart replies. "So this is just nonsense, 200 pages of nonsense? Gibberish?" wonders O'Reilly. "We think a little more highly of it than nonsense," Stewart sniffed. "We feel it's well-crafted satire speaking to the human condition, but okay gibberish is fine."

During the break, O'Reilly admired himself in a mirror, as is his wont, only to be called out for it when he played the "average American" card. "Do people know we're in a room with like eight people and you're the only one with a mirror?" Stewart prods, grabbing the mirror from under O'Reilly's desk. "This sits next to the guy talking about the folks." Then O'Reilly whines about not being invited on Oprah Winfrey's show, and Stewart explains, "She doesn't like you." "Why?" "Because you're not likable!" Oh, hell, just watch the whole thing:

The interview aired last night on Fox, and on Monday night O'Reilly will appear on The Daily Show to plug his book, Pinheads and Patriots. Show biz!