Traffic to comparison shopping Web sites increased 56% for the week ending November 3, 2007 compared to the same week in 2006, according to Hitwise.

One-fifth of visits to comparison shopping sites were to Yahoo! Shopping. Smarter.com and Bizrate were next, with 15% and 14%, respectively.

“As we enter the holiday shopping season, consumers are beginning to research potential gift purchases and compare prices earlier than last year, especially with retailers beginning to roll out seasonal promotions,” said Heather Dougherty, director of research at Hitwise.

Most of the traffic to the comparison sites came from search engines. Google accounted for 20% of visits, while 14% of the visits started at Yahoo! Search.