Fred Davis is a great guy, but his Lumeria scheme won't work. We don't think of our personal data as an integrated whole, or consider our identity a good in the marketplace. Most of us allow sites like Amazon to track us because we see the site giving us better recommendations in exchange. The idea that this data might be sold to others troubles us, but not enough to keep most of us offline. I got two free shirts and a tie, but I'm not going to be spending more there because they gave me the merchandise.
Consumers feel the same way.
We want the best price when we go to market, not before and not after. When sites demand data of casual users we click away. The key is for an intermediary to wait until I raise my hand to buy, then give me the merchants' best deal and let me make my own decision. For this to work the intermediary must first earn my trust, and preferably provide some up-front benefit. Many, many people have tried to become this intermediary, long before the Web was spun.