It took all of seven minutes on social media for fans to pay their respects to David Letterman before speculating who will take his place.

Fair enough. There will be plenty of time to pay tribute to the most influential comedian of the last 30 years over the next year. Dave could stay in his seat until August 2015 (although I'm predicting a May exit).

But let's pay tribute to the way he made the announcement Thursday night. He told a touching story about how spending time with his son, Harry, meant more to him then thinking about the show, another indication that Letterman has pulled himself out of day-to-day operations over the past few years and basically shows up and does what the writers have prepared for him.

The audience's stunned silence when he said he was retiring was the most memorable moment of the night. If viewers hadn't been signaled ahead of time, I'm sure we would have been equally speechless. But it's clear it's time for Letterman to pass the baton to a new generation, just as Carson walked out at just the right time.

I'm sure it was pure coincidence, but the melancholy performance of Lou Reed's "Take a Walk on the Wild Side" perfectly reflected Letterman's reign: A PG-rated renegade

I'll get into the replacement game later today, but for now, I'm just grateful that Letterman kept me entertained for more than 30 years - and that I get at least one more to enjoy his company.