Press release DETROIT - General Motors saidtoday said that Global Chief Marketing Officer Joel Ewanick has elected to resign effective immediately. Ewanick, 52, joined GM in May 2010 in charge of marketing for the company's North America unit. He was named global chief marketing officer in December 2010. Prior to joining GM, Ewanick was vice president of marketing and chief marketing officer for Nissan North America. Before joining Nissan, he served as vice president of marketing for Hyundai Motor America. Alan Batey, vice president, U.S. Sales and Service, will assume the role of global chief marketing officer on an interim basis.