Tonight at 11:35pm is when Stephen Colbert begins his new career as a late night talk show host. From what we can see, he is not aiming to revolutionize the format but keep it broadly similar to what been done before, the new wrinkle being that his guests would cover a wider range than just celebrities from the entertainment world, also encompassing politicians, writers, scientists, and other people of interest.
A more subtle change might arise from the fact that his background, unlike those of other late night talk show hosts, is in improvisational theater and not stand up comedy. This requires people to be very quick-witted and be willing and able to take whatever conversational gambit is offered and riff on it. A few years ago, he appeared on Bill O’Reilly’s show and he shows this skill.