Ferguson's monologues are genuinely engaging. Letterman is only good with good material, Conan was always too akward to speak at the camera, and Leno's monologues make you want to hang yourself.
Seems like the nightly monologue would be a really tough format. With skits you can take one basic joke (a relationship between characters, a list of wacky cable channels) and get five to ten minutes of material by playing with the variations. But writing enough gags to create a small stand-up routine four or five nights a week?
Conan was always good at playing off the crowd, Letterman lets you know whether he thinks a joke is good or filler, and Leno's horrible of course. I wouldn't mind if any of them dropped that part of the show (not that I've watched late night regularly in years), except Ferguson. He's funny and energetic and really into what he's doing. He can be a little preachy, though; there's more than a whiff of Olbermann there.
