He replaces the anchor team of John Dickerson and Maurice DuBois, who both left the network in recent months.
The cash and stock deal is valued at $27.75 per Warner share, giving it a total enterprise value of approximately $82.7 billion.
Former KRNV & KOLO sports anchor Bryan Samudio has passed away.
The seven-year deal has an average annual value of $1.1 billion, the companies said Monday.
Charter Communications, known more widely as Spectrum, has more than 32 million customers in 41 states including Nevada.
The New York Times reports a Nevada commissioner has ruled against Fox patriarch Rupert Murdoch, whose family trust case played out in Washoe County.
O'Donnell is becoming a special correspondent focusing on big interviews for CBS after the presidential election.
The new combined company is valued at around $28 billion.