The 52-year-old Vieira had been the subject of “Today” rumors for several months, ever since speculation about Couric’s departure heated up in January.

NBC will announce her new job at a press conference scheduled for 1:30 p.m. today. Vieira herself broke the news first on this morning’s “The View,” telling viewers 10 minutes into the program that she would be leaving the show this summer, delivering the news much the same way Couric did yesterday on “Today.”

“I’ve reached the point where I have to veer off the path that I’ve set for myself,” Vieira said at 11:10 a.m. on ABC’s “The View,” then saying she was moving over to “Today.” She received a standing ovation from the audience and a tribute from her other co-hosts.

It’s not surprising that NBC moved so fast. After Couric announced her departure, it was important for NBC to show that it was in control and fully prepared to deal with the potentially difficult situation.

After all, Couric has been on “Today” for 15 years, during which the show has built an incredible 10-year weekly winning streak among total viewers and generated some $600 million per year in ad sales. NBC wants to assure those advertisers that a plan is in place for the post-Couric years.

CBS took the same sooner-the-better approach in wooing Couric. Though her contract was not up until the end of May, the network received permission to talk with her early as it wanted to have the new position secure before going into next month’s upfront.

The warm Vieira seems like a smart choice to replace Couric. They are similar in age and temperament, and Vieira has shown herself capable of discussing anything from orgasms to organic fruit during her nine years on “The View,” ABC’s late-morning female-centric talk show created by Barbara Walters.

Vieira has actually been courted by ABC and CBS’s morning news shows in past years. She has said before that she did not want to inconvenience her family by making a big switch, but with the oldest of her three kids off to college, she apparently changed her mind. Vieira’s husband, Richard M. Cohen, has multiple sclerosis, and Vieira also spends time caring for him.

Vieira has a background in hard news, spending several years as a “60 Minutes” correspondent. Most recently she’s hosted the daytime syndicated game show “Who Wants to Be A Millionaire.” She may keep that gig until her contract is up two years from now, but syndicator Buena Vista is expected to let her go early.

She will receive a multi-year contract worth $40 million from NBC, where she’ll join co-host Matt Lauer. Her ABC contract expires July 31, but the network is expected to spring her early.

Other candidates to succeed Couric included “Weekend Today’s” Campbell Brown and Natalie Morales, a correspondent for the network.

Vieira has been the frontrunner all along. She’s considered the stable one on “The View,” giving balance to Joy Behar’s acerbic wit and Star Jones’ over-the-top rants.