OpenAI CEO Sam Altman listens to questions at a Q&A following a tour of the OpenAI data center in Abilene, Texas, U.S., Sept. 23, 2025. Shelby Tauber | ReutersThis week, OpenAI redefined what momentum — and risk — look like in the artificial intelligence arms race.Now comes the hard part: Executing on CEO Sam Altman's multitrillion-dollar vision.In a rapid-fire series of announcements, the company unveiled partnerships involving mind-bending sums of money and cemented its place at the center of the next ...