As standalone entities, each of the key emerging targeting methodologies, demographic (which tells you WHO consumers are), behavioral (which tells you WHAT they like) and contextual (which tells you WHERE they are) each have signal strengths and weaknesses.This is a great article in which Phil Leggiere, (Behaviorial Insider, Wednesday, Apr 18, 2007) asks questions of Tim Vanderhook, CEO of Specific Media, about behavioral targeting.
In the new paradigm there are still three steps, but they're very different. Now it goes more like this. You (the advertiser) tell us what customers you're trying to reach. Then we identify them -- and finally, we report on the content.