When my family first got a VCR, there were a few things I taped regularly: 1) The Simpsons; 2) anything with Arnold (come to think of it, both this one and that one); and 3) late night appearances by bands I liked. By the time I was a teen, I think Conan had started, I had figured out I preferred him over Leno and Letterman was like an acquired taste that would sneak in on occasion. Without understanding it, it was clear that each show had a different demographic.
So, it's funny now to watch a performer carry the same song through the late night circuit and trainspot the changes. And even funnier that I still generally don't like performances on Leno. Andross noted his nonna wouldn't like the Leno performance, which is surprising because it the Tonight Show is supposed to be populist and intergenerational -- as messed up as that sounds looking at Keri's bodice and slightly robotic back-up. But the line-up and sound was familiar, she looked cute, she even donned the blond wig and, to her credit, she never over-sexxed up the joint by taking off her jacket and (gasp!) showing her bare shoulders.
Whereas on Letterman, whoo... The band was revamped to retro-mode, the wig was now an up-do and Keri somehow channeled both pre-Dirty Diana and a hula dancer. Watch her making eyes with the audience after the end of the song as Letterman makes the rounds. Yikes. Can middle America even see the scandal? And Letterman's response is the coup de grace: "And we'll see you tomorrow night."
P.S. The Fader has a great bit on the Hill-Hilson love-fest. Yes, it's ok to swoon.