Is David Letterman the Super Bowl's Best Pitchman? - AdAge.com

Is David Letterman the Super Bowl's Best Pitchman?
AdAge.com
Getting David Letterman to shill for CBS in the Super Bowl is tougher than a Stupid Pet Trick. In each of the last two CBS broadcasts of the Big Game, Mr. Letterman has surprised viewers by turning up during one of the game's commercial breaks to do