GM ( GM) got a jump on everybody, distributing photos of the ATS on the eve of the press preview and formally unveiling it early Monday. Don't think being first is not important to Detroit's automakers. Ford and Chevrolet are arguing about which is America's No. 1 brand. ATS is a lightweight, rear-wheel drive vehicle with one of the lowest curb weights in the segment of less than 3,400 pounds. GM called it "the most agile and lightweight Cadillac." The most fuel-efficient ATS will get 30 mpg on the highway. The car represents GM's effort to take on BMW and Mercedes, leaders in the luxury segment, just as it took on small car makers a year ago when introducing the Cruze, which ended the year as the 10th-best-selling vehicle in the U.S. and our choice as car of the year. "It looks like they are going right for the jugular with BMW, trying to build a car that will out-handle the current 3 series," Motor Trend Editor Edward Loh said. "It's a bold assertion by Cadillac, because BMW created the sports sedan segment and Cadillac has never been a player in this field. To even talk about taking on BMW, they have to go through Mercedes, Audi and Lexus."