David Letterman walks out on Joan Rivers (VIDEO)

This week, Joan Rivers walked out on a CNN interview while promoting her book Diary of a Mad Diva. In return, David Letterman walked out on her during her interview on the Late Show!

Hilarious!

Nice of Dave to be thematic regarding Joan's promo tour for her book. Someone has to walk out.

"What was the interviewer's name?" said David Letterman referring to the CNN interview.

"I don't know." said Joan Rivers.

Letterman then left after Joan made a joke about a Depends commercial she missed out on. She then proceeded to interview herself then repeated her "dry vagina" joke which is one of her comedy staples. Well done!