Any way you slice it Jimmy Fallon is my pick for late night talk show king. He has great relationships with his celebrity guests and seems really genuine when conducting his interviews. He respects people for who and what they are and it shows when they come on and do some guest spots in skits and videos.
His latest is with Will-i-Am or however you spell it and it plays into a character he does called Sara on the show. Brilliant again Jimmy Fallon, just brilliant.