He will be replaced by "Good Morning America" co-anchor Diane Sawyer.
Gibson has anchored "World News" since 2006, and was a co-host of "Good Morning America" for much of the 20 years before that.
He will be replaced by "Good Morning America" co-anchor Diane Sawyer.
Gibson has anchored "World News" since 2006, and was a co-host of "Good Morning America" for much of the 20 years before that.