Online channel-management platform Mercent said same-seller GMV (gross merchandise volume) of its clients participating in Amazon's "Selling on Amazon" third-party marketplace program increased 56% on Black Friday relative to 2008, and increased 78% on Thanksgiving day relative to 2008. This is compared to overall same-seller online retail GMV growth of 41% on Black Friday and 33% on Thanksgiving.

According to Mercent CEO Eric Best, the improvement in 2009 confirms his belief the retail industry, especially online, is in a measured recovery, and he expects the growth to continue on Cyber Monday and through the peak selling season in December.

Mr. Best also said consumers are responding well to aggressive merchant promotions, discounts and increased customer service levels offered online. The company attributes merchant GMV sales growth across online channels to several factors:

• the macro-economic recovery in non-discretionary and discretionary spending;
• the increased draw of online channels that provide aggressive and competitive purchasing options for value-conscious shoppers;
• and the efficiencies of major online shopping destinations such as Amazon, eBay, Walmart and others, that are placing downward pressure on industry selling and fulfillment expenses.

Mercent Retail helps leading online retailers promote their products across online transactional marketplaces including Amazon and eBay. Mercent did not break out its merchants' eBay results.