What is there about the images that would be so hard to believe? Is this some type of ideological meme? A guy shaves his head, grows facial hair? Maybe the suggestion is he's a Hollywood liberal, gone to pot, when in actuality he looks pretty healthy.
In the bottom photo, Letterman looks like he's vacationing in a place most people here could not afford to visit for a day, let alone vacation in. Read the text on the door behind Letterman. In the top photo he looks like an old white guy, knowing he's had heart issues, taking exercise seriously.
What is the point of this thread? What is there about the images that would be so hard to believe? Maybe the title should read
"For some obscure and unmentioned reason, I can't Believe What David Letterman Looks Like Today....."