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The increasing popularity of customer reviews on retailer sites and elsewhere, she said, "will help get customers a little more engaged, and thinking about recommendations from other people, which is what ThisNext and these other sites are based on."

Fox was set to release "Alien Vs Predator" on D-VHS the same day it released "I, Robot" on D-VHS and claimed the title to be available on their retailer site.

These sites do not "aggregate" data-feeds provided from the retailers, they search and retrieve the data directly from each retailer site.

Shoppers can click on an item on the site, which links them to retailer sites like Nordstrom, Macy's and the Gap to make the purchase.

Conceptually similar to Google AdWords, PIXSTA AdImages generates revenue from the advertisers in the form of click-throughs, which take the visitor directly to the appropriate product page on the retailer site.

"That growth rate is coming off of a smaller base, but I do believe that shopping comparison will be more highly used by consumers as they get used to seeing more features like this on retailer sites," she said.