A few weeks ago, 32% of our readers said they wouldn't shop at Macy's this year for Black Friday, based on past experiences. This week, a petition is circulating that demands Macy's cease its relationship with Donald Trump, after the real estate developer criticized Barack Obama via Twitter. Could the Trump association be the final straw for those who are hesitant to give their business to Macy's? And will the retailer's Black Friday sales suffer?