In journalism, the competition to pick the new editor of a magazine or newspaper is often called a “bakeoff.” (The oven is now preheating at Vanity Fair, following the announcement that Graydon Carter, the magazine’s editor since 1992, will step down at the end of the year.) It also seems a pretty good way to describe the unusually public process Amazon and its founder, Jeff Bezos, have cooked up to select the city where it will locate a second headquarters, building on its presence in Seattle.