This will be short as the show hasn't aired yet. I saw a report on The New York Times' site about McCain's re-union conversation with Letterman.
In it, he apparently owns his mistake:
Mr. Letterman got right to it: "So what happened?"
Mr. McCain answered: "I screwed up."
But he makes sure to deflect any further critique of his behavior.
After the audience applauded, he continued, "Look at all the conversation I gave you. Including having Mr. Olbermann on."
(The MSNBC anchor Keith Olbermann filled in for Mr. McCain at the last minute on Sept. 24. On Thursday, Mr. Olbermann was shown standing backstage, ready to appear again if the candidate had not arrived.)
Mr. McCain added: "I haven’t had so much fun since my last interrogation."
Sheesh. This is one hell of a reproductive rabbit that he pulls out of his hat.
(I'll post video when it's available.)