They often throw barbs at each other when on their own shows, so when Jon Stewart and Bill O'Reilly are on each other's sets, it's always compelling. But surprisingly, when face to face, they jab and spar rather playfully and demonstrate little true dislike for one another (even if Stewart seems to get the best of O'Reilly more times than not). Each has been on the other's show multiple times since 2001, and probably the most in-depth political discussion was on The O'Reilly Factor early this year. But perhaps the funniest exchange was the most recent. Stewart went on The O'Reilly Factor in September to promote his new book Earth while O'Reilly appeared on The Daily Show for his book Pinheads and Patriots. However, Stewart had a special introduction for O'Reilly, complete with a singer who belted out a song for the Fox News commentator as O'Reilly strode through a trail of rose petals. O'Reilly didn't seem all too amused by the welcome, which was in response to his own curt, unwelcoming introduction a few days earlier, which was simply, "Stewart's back."