Keynote Competitive Research, the industry analysis group of Keynote Systems, came up with the U.S. Holiday Impact Study that monitored the technical performance and service levels of 26 leading retail Web sites during the 2007 holiday season. According to Ben Rushlo, senior consulting manager for Keynote’s competitive research group, there is an overall improvement in performance of sites across the retail industry as compared to last year.

The study included leading sites across all major retail categories such as Amazon.com, Barnes and Noble, Best Buy, Home Depot, Target, Toys R Us and Wal-Mart.

Cabelas, Barnes and Noble and Best Buy were sites that were highly available with little or no downtime over the 30 days study period.

Victoria’s Secret, Circuit City and Cabelas were the most responsive sites as they were fast in downloading pages and completing transactions for consumers. Cabelas and Best Buy shared the crown for best overall service levels as they towered over other sites in terms of both site reliability and responsiveness.

The best technical quality performance was rendered by the electronics and books and music retailers while the home improvement industry exhibited the worst performance.

Almost 30% of all holiday shopping is done online, and that figure continues to increase, according to the National Retail Federation. Low performance is suicide for retail sites especially during holiday season when they can actually capitalize on sales. Some of the leading retail sites showed up to 400% slowdowns during peak shopping days, prompting consumers to abandon their product search.

Thus, the time has come for web sites to invest their time and energy on web performance tuning.