CBS Corporation and Warner Bros. Entertainment rocked the broadcast television landscape this morning, making an unexpected and somewhat shocking announcement that they will be shutting down their respective UPN and The WB networks and instead launching a new The CW broadcast network that will begin operation this fall.

According to the surprise announcement -- which comes just days after both networks had supposedly outlined their future plans to reporters during the semiannual two-week Television Critics Association Press Tour that just concluded on Sunday -- CBS and Warner Bros. will each own 50% of the new network, which will air some still undetermined combination of UPN and The WB's current television programs (which in include current reality shows such as America's Next Top Model, Beauty And The Geek, and previously announced upcoming shows such as Get This Party Started, Fountain Of Youth, Survival Of The Richest, and another gender-reversed edition of Beauty And The Geek.)

"This new network will serve the public with high-quality programming and maintain our ongoing commitment to our diverse audience," said CBS Corporation president and CEO Les Moonves. "It will clearly be greater than the sum of its parts, delivering excellent demographics to advertisers, and building a strong new affiliate body."

The CW is expected to be available in 95% of the country, with Tribune Broadcasting (The WB's big affiliate partner) and the CBS Corporation's UPN affiliates having already separately agreed to sign 10-year affiliation agreements with the new network. The combination of Tribune's 16 major market stations and the 12 CBS-owned UPN major market affiliates has instantly given The CW coverage in 48% of the country, with the addition of other select current UPN and The WB stations expected to allow the new network to reach the 95% figure.

Current UPN president Dawn Ostroff will become the new network's President Of Entertainment while John Maatta, The WB's current COO, will assume the same position for The CW. The CW will incorporate The WB's current scheduling model -- a programming lineup that, unlike UPN's current schedule, not only offers Sunday night primetime programming, but also includes weekday afternoon and Saturday morning programming blocks. Altogether, The CW will air thirty hours of weekly programming.

According to CBS and Warner Bros, Ostroff -- the new network's top creative executive -- will be able to move whichever UPN or The WB current shows that she wants over to The CW. "It's a scheduler's dream," Moonves gushed at Monday's news conference announcing the new network. "The CW will be able to do something truly remarkable -- program already hit shows every single day of the week, programs that consistently rank #1 or #2 in their time slots in the most coveted young adult demographic."

However, while it's reasonable to expect that top shows like Top Model (which Ostroff announced she had already renewed for two more seasons when she met with reporters at last week's UPN press tour presentation) will migrate over to the new network, it is currently unknown what the new network's fall schedule might look like. Both America's Next Top Model and Beauty and the Geek (along with Smallville, Gilmore Girls, Supernatural, Veronica Mars, Everybody Hates Chris, Girlfriends, Reba and the WWE's Smackdown) were cited as examples of the "programming assets" available to the new network -- a sign that CBS and Warner Bros. envision both shows as having a place on The CW's future programming schedule.

Less clear is the fate of more recently announced new The WB reality projects such as Survival of the Richest (which current The WB president David Janollari -- whose own future with the The CW has yet to be determined -- announced at last week's The WB press tour presentation) and Beauty And The Geek co-creator Ashton Kutcher's new The Amazing Race-like Fountain Of Youth (first announced back in October.)

One thing the new network plans will not effect is either network's current season programming plans. According to CBS and Warner Bros., UPN and The WB will both continue to independently broadcast their own network schedules until The CW launches this fall, which means that neither Top Model 6 (premiering March 8) or Get This Party Started (premiering February 7 and co-hosted by Laguna Beach's Kristin Cavallari) will see their broadcast schedules changed.