Web Analytics PRIZM (not Prison) is using Geo-Demographic segmentation systems in Web Analytics such as PRIZM.  There's a short post on this subject in Analytical Engine today.

"..Jim Novo, who authors an insightful marketing blog, rightly identifies that PRIZM clusters (or other geodemographic segmentation systems) are not as predictive as a behavioral data for desired ‘action’ in the online world.

e-commerce folks are usually looking for behavior from customers, and the fact demographics are not generally predictive of behavior by themselves

I have done some work in Search Term Research using Geo-Demographics via Microsoft AdCenter and whatever other Geo-Targeted info I could get ahold of; I was able to get some very interesting data that was thought provoking but not really predictive of how people would behave or why.