Shoppers look over advertisements flyers as they shop for merchandise at a Best Buy Co. store ahead of Black Friday in San Francisco, California, U.S., on Thursday, Nov. 27, 2014. An estimated 140 million U.S. shoppers will hit stores and the Web this weekend in search of post-Thanksgiving discounts, kicking off what retailers predict will be the best holiday season in three years. Photographer: David Paul Morris/Bloomberg via Getty Images