Jay Leno

NBC announced Jay Leno's new 10 p.m. show as a win-win: a way to keep a bankable star on the air while unveiling an entirely new way to look at prime time scheduling.

The question now is whether the new show will be as good – and earn the ratings – of the shows it will replace in prime time. Monday through Friday, he'll occupy a full third of the 8-11 p.m. bracket when most people watch TV.

Leno consistently wins his late-night slot, and the show should also be cheaper to produce than the original dramas that usually fill the time – including ER, now in its last season.

And while the show will bring more stability to NBC's lineup, it will also mean less diversity: one show, using many of Leno's routines from the The Tonight Show, instead of five different programs.

NBC chief Jeff Zucker set up the announcement Monday by saying he believes all networks may eventually have to scale back the number of hours they program.

"As broadcast television continues to change, success demands a new paradigm," Zucker said in a statement Tuesday. "For the past few years, we've been very vocal about two things: Transforming broadcast television for today's media landscape, and keeping Jay at NBC. In this one announcement we have done both. It's great for NBC, for our viewers, and for our advertisers."

NBC says the show will include Leno's familiar format of a monologue, guests, and routines like "Headlines," "Jaywalking" and "Battle of the Jaywalking All-Stars."

As has been planned for months, Conan O'Brien, will replace Leno on The Tonight Show on June 1, 2009. Leno's contract expires in a year and a half.

Sliding into O'Brien's time slot starting March 2, 2009, will be former Saturday Night Live star Jimmy Fallon, who on Tuesday introduced his first vlog for the show and its new house band, hip-hop icons The Roots.

Leno took over as host of The Tonight Show on May 25, 1992, taking over for Johnny Carson.

What do you think? Are you happy to trade five hours a week of other programming for five hours a week of prime time Leno?