Online retailing is in the midst of rapid advances as companies improve their ability to monitor customer behavior. "Web analytics allows retailers to predict what customers might want to buy next by looking at their past purchasing history, as well as data generated from other shoppers," according to a new piece in Business Week. "It also helps companies make important improvements in how easy their sites are to navigate and use."

Coremetrics and Omniture, for instance, are selling their hosted, site analysis services for fees ranging from $30,000 to $100,000 a year. Sportsline.com has used Omniture's SiteCatalyst to identify when customers "dropped out of signing up for its fantasy football league, allowing Sportsline to improve its process and increase the number of paying customers."