David Letterman Is Properly Medicated Now

David Letterman was king of late night television for 30 years. Now he's figuring out his second act.

"He and the writers of [Late Night with David Letterman] changed the sense of humor in the United States," says Jimmy Kimmel, a big Letterman fan. "It was a revelation in a lot of ways. You could really only compare it to music, bands like The Beatles and Elvis, where things actually changed."

Letterman reflects on the "late night wars" with Jay Leno, the new beard, and his comedy heroes. But Letterman's favorite thing? Being a dad to his son, Harry.

"I wish I had a sibling for Harry" he told Geoff Edgers, from the Washington Post, in the season finale of Edge of Fame.