The digital revolution is transforming the relationship between consumers and companies. Nearly all business functions are feeling the effects, but conventional marketing sits squarely on the fault lines of disruption. Brand-authorized messages increasingly can’t compete with online customer ratings and reviews—neatly packaged and aggregated on sites like Amazon—in terms of authenticity. Online feedback even promises to infiltrate the physical shopping experience: e.g., the shelves at Amazon’s new brick-and-mortar bookstores proudly display the scores of highly rated titles.

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