To my surprise, Letterman is shaving the beard on tonight's program.

I suppose his wasn't a "strike beard" like Conan's as he never specifically referred to it as such. I can just picture something later like:

Dave: Well, you know, Paul, I had to shave it.
Paul: aww, why?
Dave: It was getting on my nerves...gettin' on my nerves.
(makes shoulder-slumping forward motion and shakes his head while making a face)...The truth is...is that punk Conan O'Brien has a beard now too, ya know?

It won't happen, but anyway...

...