Is Google's Behavioral Targeting A Bust? Only 25 Percent Of AdSense Publishers Use It

For advertisers on the Web, behavioral targeting is held out as the nirvana they've been waiting for: the ability to show ads only to those people most likely to be interested in them based on their past behavior. The growth of this type of ad targeting also raises a host of privacy concerns, but setting those aside for a second, do these ads even work? Do they perform better than regular ads? If they did, you'd expect advertisers to pay more for them and for Website publishers to be flocking to them.

At least for Google, the answer seems to be "No." According to estimates by Jim Brock, founder of PrivacyChoice, chairman of Attributor, and a former senior VP at Yahoo, only about 25 percent of AdSense sites are serving targeted ads, which Google calls "interest-based advertising."