There is a huge effort in the market for ecommerce site to improve their conversion rates, not surprising given the huge amounts of money paid in search advertising and commissions paid through the affiliate channel. Check out 7 Billion People, they are based in Austin Texas and have been working on dynamic web content based on how people prefer data to be presented and alert to how people make decisions differently. They claim to improve conversion rates by 10%+ which of course is a huge amount for large etailers.