Behavior trumps demographics in the new era of intelligent measurement. Overstock.com, an Internet retailer of discount merchandise, assesses behavioral clusters to determine where to invest its market dollars.

"When you add up everything you know about your online customers, you can get rid of education, income, children, and the rest of the demographics,” said Overstock CEO Patrick Byrne in a speech at the Web Analytics Summit at eTail 2004. "Demographics are foggy data. You can only guess and surmise why people who live in the same Zip Code might or might not shop the same way, want the same stuff or be willing to pay the same price. But behavior data is sharp. Customers' behavior is a signpost to their needs, so we don't cluster people based on who they are or what car they drive, but by their needs as expressed through their behavior.”

We appear to have entered an era of remarkable customer surveillance and this can be expected to transform marketing as we go forward. As Jim Sterne, president of Target Marketing, puts it at CRM Guru: “How an individual uses a retail site provides more insight into how they might be persuaded to buy than their martial status, age, or whether they bicycle to work or take the bus.”