A throng of fans crowded the sidewalks outside the theater, where Letterman has hosted the show since 1993.
Letterman is retiring after 33 years in late-night TV. He has hosted 6,028 broadcasts on
CBS promised only "surprise guests," but the musical act was confirmed to be Foo Fighters, the rock band led by Dave Grohl, which is a longtime Letterman favorite.
The show's Twitter account, meanwhile, promised "free balloons for the kids!"
The hashtag #ThanksDave was trending on Twitter.
What do you think of Letterman's exit from late-night TV?