Google alone sent e-commerce sites 14.93 percent of their U.S. traffic for the week ending Aug. 26, according to Hitwise. Last year, the search giant accounted for just 9.45 percent of visits to shopping and retail sites during the corresponding week. Yahoo Search was responsible for 4.69 percent of visits for the week ending Aug. 26--up from 3.72 percent last year--while MSN accounted for 2.33 percent, up more than threefold from 0.73 last year.

But it's not just search engines that send traffic to e-commerce stores. Social networking site MySpace--which has continued to balloon in traffic this year--accounted for 2.53 percent of traffic shopping sites for the week ending Aug. 26, up from 1.28 percent six months prior.

What sites did MySpace send visitors to? The top shopping/classified sites that were visited immediately after MySpace include eBay, Amazon.com, Gateway, Walmart.com, and Craigslist.

Separately, Hitwise Friday released data showing that MySpace isn't just sending traffic to e-commerce sites; it's also sending news sites 1.39 percent of their traffic--up from around 0.8 percent six months ago.

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