Todd begins his new role on Sept. 7. He remains as NBC News' political director, but will relinquish his duties as Chief White House correspondent and anchor of MSNBC's The Daily Rundown. He has been a frequent guest on Meet the Press as a political analyst.
The 42-year-old Todd came to NBC in 2007 after working for National Journal's The Hotline, where he was editor-in-chief.
He becomes only the 11th permanent host of Meet the Press, which premiered in 1947 and bills itself as "the world's longest-running television program."
Gregory had been moderator since 2008. Before that, he was NBC's Chief White House Correspondent for the eight years of George W. Bush's presidency. He had been with NBC News since 1995.
The announcement by NBC News president Deborah Turness ended months of speculation that Gregory's time was running out on the program, which during his tenure has fallen from first to third place, ranking behind CBS's Face the Nation and ABC's This Week.
The Tall Shadow of Tim RussertIts ratings erosion felt even more pronounced since Gregory had followed the late Tim Russert, a popular, larger-than-life figure who became almost as much an institution as the program over which he presided for 16 years. He was its longest-serving moderator until his sudden death in June 2008. Under Russert, the show was by far the dominant program in its category.
"I'm not Tim," Gregory told viewers when his Meet the Press appointment was declared. "But I can just work real hard to make him proud."
In February 2013, the network signed Gregory to a new contract it described as "a long-term commitment."
But one published report in recent months stated that Gregory would be replaced after the midterm elections. And a story published in April by The Washington Post said that NBC commissioned a "psychological consultant" to interview Gregory's wife and friends.
NBC responded that it had simply worked with a brand consultant probing perceptions of Gregory's strengths and weaknesses to develop a marketing campaign.
At the time, Turness was moved to defend Gregory with a memo to the Meet the Press staff expressing support "for the show and for David, now and into the future."
Gregory 'Humbled and Grateful'In Thursday's memo, Turness offered her "sincerest thanks" to Gregory, while declaring that Todd "will ensure that Meet the Press is the beating heart of politics, the place where newsmakers come to make news, where the agenda is set."
This official word followed by a couple of hours a Twitter post by Gregory himself that he was departing: "I leave NBC as I came – humbled and grateful," he said.
NBC News correspondent Andrea Mitchell will serve as moderator this weekend, Turness said in her statement, adding that Mitchell will "continue to be a central figure of the broadcast, along with some new names that we will announce in the coming days."