Costco's search engine is poorly designed and the Web site overall doesn't engage the user. Best Buy's offline stores may perform better, but online the retailer lost out to Circuit City in terms of customer support, visual appeal and the purchase process.

The visual appeal of Amazon.com really stood out. The site offers 360-degree viewing of products and very detailed descriptions. The one-click checkout process is efficient and easy to navigate, and its search engine is pretty fast.