We've all heard the news by now that David Letterman announced last night that he's retiring sometime in 2015. No exact date has been set, and I'm sure Dave will have loads of fun on the way out the door. Let's face it, he's made his mark by being pretty aloof about everything. With an exit ramp in plain view you know that whatever few limits he's imposed on himself will be gone. Were you there when Dave's late-night legacy began? It was on NBC in 1982 with very first guest Bill Murray.