You’ve finally embraced e-commerce. But are you ready for m-commerce? How to prepare for the next revolution in retailing.Shortly after Blue Nile released its iPhone app, CEO Diane Irvine was hit by a “revelatory moment” about the power of smartphones. The company’s mobile app now drives 25 percent of its traffic. But even Irvine was startled when someone pulled the trigger on a $40,000 stone—from a ski lift.Mobile phones have “really changed the game,” Irvine told ­analysts at the company’s Feb. 10 conference call. “We see this as just exploding.”The growing use of smartphones—which Nielsen predicts will outnumber other types of phones by year’s end—has profound implications for the way people live, interact, and shop. (The category includes BlackBerrys, iPhones, and Android-based devices.) Smartphones and tablet computers like the iPad give users the equivale