This week American Express rolled out its new Plenti rewards program, a flexible system that allows shoppers to earn points at one business and spend them at another. So you could, for example, buy gas from Exxon or cell service from AT&T — and then use those points for purchases at Macy’s or Rite Aid. The new program comes in the wake of recent news that Amex and Costco are terminating their longtime partnership.
