Letterman and Conan. Leno recycles too many monologue jokes. The puch line may be different, but the setup is always the same. Kilborn isn't bad, but I hate watching him put his mac on with his with his female guests. Conan has some of the most hilarious antics I've seen on TV, and delivers them pretty consistantly. Letterman, what can I say, he's just the man.