Surprise! Savannah Guthrie to Co-Host 'Today' Friday

The transition at Today will be on display Friday morning.

Sources confirm that Savannah Guthrie will co-host the show alongside Matt Lauer. It is a role Guthrie has occupied on many mornings as a substitute for Ann Curry, who bid a tearful farewell to viewers on Thursday's show.

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But a formal announcement about Guthrie's role is not expected during the program.

Guthrie was offered the job last week, while NBC News executives were hammering out a new position for Curry.

Getting the new Today team in place in time to take advantage of the ratings bump from NBC's coverage of the London Olympics is a priority.

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Curry will travel to London for the Games. Meredith Vieira, Curry's Today predecessor, will co-host the Opening Ceremonies with Lauer and Bob Costas.

Guthrie, who is also Today's chief legal analyst, appeared during the 7 a.m. hour of Today on Thursday to discuss the Supreme Court's decision on President Obama's Health Care Reform Act.

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She was not in the studio for Curry's emotional farewell. But she returned for the 9 a.m. hour, which she regularly hosts with Al Roker and Natalie Morales. Lauer also stuck around for Today's continuing coverage of the Court's decision.