CBS announced today that the "Late Show with Stephen Colbert" will premiere on Tuesday, Sept. 8.

However, there are still a lot of unanswered questions about the show despite the fact that its premiere is well under a year away.

For instance, CBS executive Nina Tassler said that Colbert's staff has only started to iron out the details in terms of how the show will work and be presented. She made her remarks at the Television Critics Association's winter TV previews.

"They've actually just moved into their offices," she said. "They've just started working. He will have music on the show. He said, 'I have to be entertaining as my guests,' so he's going to have guests on the show. Whether or not he's going to start with a monologue, he's working on that right now. Clearly he knows that he's introducing himself, the real Stephen Colbert to his audience. He's really putting a lot of attention on making sure that the show is still topical and still relevant."

Meanwhile, after 22 years of hosting "The Late Show," legendary host David Letterman will record the last show from its home, the Ed Sullivan Theater, on Wednesday, May 20.

To fill up the time between Letterman's departure and Colbert's September debut, Tassler said that CBS will re-run encores of original shows during the summer in the slot that's currently occupied by Letterman. There also may be some Letterman specials in the run up to May 20.

Tassler had glowing things to say about the new incoming "The Late Late Show" host James Corden, referring to him as a mix of of Jack Black and Fred Astaire.

"James came into the room, and to say we were mesmerized by him was an understatement," she said. "What he demonstrated in that room when Leslie [Moonves] and I met with him, you couldn't take your eyes off of him. He's so vibrant, he's so entertaining. He's a fearless actor. He's pretty magic. It doesn't matter who he talks to, they just fall under his spell. He's enchanting."

Corden's tenure as host of "The Late Late Show" will begin on Monday, March 9.

Meanwhile, Colbert responded to the news of his CBS debut date in a way that only he could.

"I have nine months to make a show, just like a baby," Colbert said. "So first, I should find out how you make a baby."