[ Photo courtesy of S. Shepherd via creative commons license. ]

Online shopping traffic from Facebook and Twitter has grown in the last year, but still represents less than 1% of total ecommerce traffic, according to a recent report.

RichRelevance, an online personalized shopping retailer, collected data in August from 200M+ shopping sessions, which resulted in sales of $500M+, to see how Americans browse and shop for products online.

Facebook is growing the most dramatically of any traffic source for online shopping, according to the study. The social network increased its contribution by 92% between Aug. 2010 and Aug. 2011. The study also looked at traffic from AOL, Bing, Google and Yahoo.

Although shoppers who are directed to retail sites from Facebook and Twitter are less likely to make purchases, they end up spending more per order than shoppers who come through Google, according to the study. Shoppers directed from Twitter had the highest average order value -- $121.33 -- of all shoppers.

Online shopping traffic from search engines AOL, Bing and Yahoo together accounted for 18% of all traffic to major retailers in Aug. 2011, but Google alone accounted for 81%.

Consumers spend an estimated $450B on holiday shopping, but spent less on each online purchase than last year, according to RichRelevance.

Social media sites are not yet a significant source of traffic for retailers, but Americans spend more time on Facebook than any other site [ see our story here ].

"This data is a wake-up call for brands who want to reach holiday shoppers who are congregating in the online shopping channel," RichRelevance CEO David Selinger writes. "This is the time to focus on new ways to reach and influence consumers directly on retail sites, at the point of purchase, when they are ready to buy."

Have you made any purchases at online shopping retailers through Twitter and Facebook? Let us know in the comments.