The production company was crucial when Letterman moved to CBS two decades ago.

…But some shows have made the transition better than others.

Listen to some bonus audio before the whole conversation airs Friday.

Half a billion dollars of advertising is at stake in what is now a three-way competition among Jay Leno, Dave Letterman and Jimmy Kimmel. One show's response to Kimmel's challenge: shave a minute off its start time.

Late night TV is about to go where it's never gone before. ABC says starting in 2013 it's moving 'Jimmy Kimmel Live' a half hour earlier, to compete head-to-head with Letterman and Leno.

Are you with Coco? After Conan O'Brien was ousted from NBC's "Tonight Show," many speculated that he would head over to the Fox network. But in a…