David LettermanÂs departure isnÂt the end of an era. The era of late night talk shows ended a while back. In Johnny CarsonÂs final week in the nineties, he played to an audience of twenty million. Lately, Letterman has been lucky to get 2 million. His final shows have played to around 5 million viewers.Late night talk shows still exist, but their intended audience mainly watches viral clips from them the next day.