Social media agency Big Fuel has been dropped from General Motors’ roster, becoming the first loser in GM’s global review. Its duties will be split among the creative shops for Chevrolet, Cadillac, Buick and GMC. Big Fuel will keep its Detroit shop open, despite the loss, for clients such as McDonald’s. “This is the world of marketing. It’s challenging, but it’s not discouraging,” Big Fuel’s Seth Berk said in his recent interview with Michael Kogan.