Who is David Gregory?

David Gregory was the $800 clue on Jeopardy! today in the category “TV Hosts by Initials.” The reigning champion named Amy was running the category, getting all the clues correct, including “Who is David Gregory?” But no one got the $1,000 clue, “Extra” and “The X Factor” host M.L. Of course, the question is “Who is Mario Lopez?”