GRAPEVINE, Texas, Sep 16, 2011—GameStop Corp., the world’s largest multichannel video game retailer, is thrilled to announce that its PowerUp Rewards loyalty program, designed with Brierley+Partners (B+P) and launched in October 2010, has won the 2011 COLLOQUY Award for Loyalty Innovation in Retail. Voted on by thousands of industry experts, this distinguished honor is the latest in a string of successes for the new loyalty program, which....