Adweek has a list of Stephen Colbert's first week guests, and it's already pretty clear it's going to be a slightly different kind of show than that time slot normally sees...
"Colbert's first guest for his debut show on Sept. 8 is George Clooney. GOP presidential candidate Jeb Bush will also appear on Day 1, along with a musical performance by Jon Batiste and Stay Human. On Wednesday, actress Scarlett Johansson and SpaceX and Tesla Motors CEO Elon Musk will be Colbert's guests, followed by another hot startup name on Thursday: Uber CEO Travis Kalanick. Comedian Amy Schumer and author Stephen King will be on Friday's show, as well as an interview with and musical performance by Troubled Waters. Grammy winners Kendrick Lamar and Toby Keith will also perform during the first week—Lamar on Wednesday and Keith on Thursday."