While marketers grapple with the usual challenges -- competition, accountability, wrangling new technologies -- perhaps they should be more concerned with a far more powerful phenomenon: informed skepticism. In a world where buyers are continuously in touch with other buyers and claims are publicly deconstructed by anyone and everyone, marketers' toughest job may be to simply convince buyers that they speak the truth. In such a world, marketing integrity is not just a virtue; it is a driver of choice.