The 11pm time slot sits on cable schedules "like a prize," but none of the networks have put live programming in it.

After all, "it requires a real commitment of resources," MSNBC president Rick Kaplan said. "It's cheaper to just run your schedule, turn it around and run it over again."

But that will change on Monday, August 8, when The Situation with Tucker Carlson moves to late-night.

"I told the network back in December or January that we were going to do an 11pm show," Kaplan told TVNewser this afternoon. "What we really created for Tucker was a late-night show, but the hole in the schedule at that moment was nine, so we figured 'Okay we'll premiere it, we'll fill the schedule.'"

Once Rita Cosby signed with the network, it was prime time for a shakeup.

"Everybody at our network loves the idea of going to 11pm. The HUT levels are pretty much the same and it's a really strong time slot," Kaplan said, noting that 15 to 20 percent of MSNBC's audience comes from the West Coast.

Kaplan said he's been pleased by "the progress" of MSNBC's primetime ratings. The Situation has averaged only 201,000 viewers since it premiered.

"I know how difficult the 9pm time slot has been -- frankly, they're all difficult time slots -- but I think Tucker has done very well," Kaplan said. He referenced the comments, on this blog and elsewhere, that it takes time to develop a cohesive panel of commentators.

The first question to Carlson was obvious: Are you ready to go up against Jon Stewart?

"Jon Stewart's got a funny show, Jon Stewart's a funny guy" -- when he's not acting like an associate journalism professor, Carlson said. "I think we're going after a different audience."

Broadcasting & Cable says the move appears "to be a vote of low-confidence for Tucker Carlson." But Kaplan and Carlson say that's not true: The bow-tied host discussed a late-night show with Kaplan before he even came to MSNBC. "This is what I've wanted to do for a long time," he said.

He continued: "This is a chance for Fox viewers, CNN viewers, people who are tired of reruns, to find a first-run program...It's a huge move, from my perspective, on MSNBC's part. As Rick said, it's a commitment of resources. It's a big deal. Other networks haven't wanted to do it because it costs money, but MSNBC is bold enough to do it."

> Update: 11:50pm: HUD has been changed to HUT. Thanks to the e-mails for pointing out the error; I published this quickly...