In a World Without Tracking & Cookies, Can Online Commerce Succeed?

Tracking consumers' behavior via cookies is creepy, and increasing numbers of the aforementioned consumers are getting fed up with it.Legislators around the world are cracking down on tracking, as well, and many browsers are making it possible for people to simply opt out of tracking via cookies.

So how could online commerce, much of which is based on a cookie-fed understanding of browsing and purchase behavior, survive in a cookie-free world?