Kelly Ripa's new 'Live' partner: Ryan Seacrest

Somewhere, Brian Dunkleman is just shaking his head.

Ryan Seacrest, whose brief cohosting gig with Dunkleman ended with Seacrest as solo host of American Idol for the rest of its long run, is Kelly Ripa's new on-air partner.

The fact that the news had leaked earlier Monday morning,  reported by CNN, didn't change Ripa's spirited introduction, which began with a cold open in which she appeared to be addressing the mystery cohost.

The host of Live with Kelly (9 a.m., 6ABC), now Live with Kelly and Ryan, had teased her 1.6 million Twitter followers Sunday, telling them to tune in Monday for a big announcement.

The South Jersey native first entered alone, thanking both the audience and the men and women who'd cohosted with her since Michael Strahan left a year ago this month, after the announcement that he was going to ABC's Good Morning America.

After the first commercial break, she returned, hand in hand with Seacrest, who, next to Ripa, looked, if not tall, at least taller. The way the two talked about it, it seemed the announcement might have been in the works for a while.

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Ripa and Seacrest  have been friends for years, and when they found out he'd be her cohost, "we were told to keep it a secret," he said.

"In our house, we don't call it a secret anymore. We call it a Seacrest," joked Ripa, who said her three teenagers managed to keep the news quiet.

Ripa's ability to appear totally open about her personal life has been a strength on a show that strives for intimacy with its audience. Monday, she noted, was also her 21st wedding anniversary, for which her actor husband, Mark Consuelos, was out of town, working.

Will Seacrest be the same? At one point, he joked that after he'd emailed friends that he had good news, their responses had been to assume he was engaged, having a baby, or coming out of the closet.

"All those things are possible for you," Ripa assured him. "This is a safe, safe place."

Seacrest, ABC said, will continue to host and produce his Los Angeles morning drive-time radio show, On Air with Ryan Seacrest, from a new iHeartRadio studio in the New York ABC7 building that houses Live with Kelly and Ryan.

Seacrest told Ripa he'd be "frequent-flying," returning to his Los Angeles home on weekends, and asked advice about being a New Yorker.

"Get to know your subway system," she said, noting that there are days, such as when the president is in town, when the subway's the only way to get places.

Seacrest will also continue his other gigs, hosting and producing E!'s Live from the Red Carpet shows and ABC's Dick Clark's New Year's Rockin' Eve with Ryan Seacrest.

Richard Curtis, the Souderton Area High School teacher who won a contest to guest-host with Ripa last year, understood her decision not to choose him. "I think it was a great decision by Live to put Ryan in the chair, he'll bring a lot of energy and professionalism," Curtis said. "I am a little let down but I try to live by the quote, 'If you're going to lose, lose to Seacrest.'"

Updated to include Monday-morning announcement.