Article provides an overview of the marketplace of ideas, its relevance to media mergers, and the current approach under the federal antitrust agencies' Horizontal Merger Guidelines. The article examines the legal support for the proposition that antitrust analysis of media mergers should be expanded to include the merger's impact on editorial competition. After finding legal support in the legislative history and Supreme Court decisions, the article explores the pros and cons of evaluating a media merger's impact on the marketplace of ideas, and asks whether this should be left to the FCC. The article concludes with several modest proposals as to how such editorial competition and the marketplace of ideas might be incorporated into antitrust analysis.