I used to watch Lettermen too, eons ago.
To me in this case he appeared as a tool and a jerk, but Cain scored way more points than Lettermen.
Cain got some talking points out, improved his image and got more name recognition.
He also slapped down the number of women to 2, and media and rats heard him. I also think that is a good thing, assuming he is being truthful.
Actually, he knocked the number of women down to 2 liars. Even better.