Each year since 2006, Amazon.com has restricted third-party sales in the Toys & Games category to pre-approved sellers during the holiday shopping season, but this year, there's a new twist. In its email letter to sellers this week, Amazon.com said orders fulfilled by Amazon would not be subject to the holiday season restrictions, provided their accounts remain in good standing.

Amazon.com offers a fulfillment service to third-party sellers and has been heavily promoting it - now it its giving sellers yet another strong incentive to use it. Its efforts have been working, with more sellers testing out and using the FBA service for at least part of their inventory. Amazon.com told Wall Street analysts recently that it was building 13 new distribution centers this year worldwide (it gave no specifics about size or location of the warehouses).

Amazon.com has always processed buyer payments on behalf of sellers, and with FBA (Fulfillment by Amazon), it knows not only if the buyer has paid, but if the item from the third-party merchant has shipped. This gives it a critical edge over competitor eBay, which continues to grapple with dispute resolution issues.

Amazon.com no longer posts announcements such as these on its Seller Announcement board; here is last year's announcement, and sellers are discussing this year's announcement on the Amazon Seller Soapbox discussion board. Amazon seller and author Steve Weber posted the entire letter on his blog.

The email told sellers that as part of the steps they could take to remain eligible to sell in Toys & Games throughout the holiday season, they could "utilize Fulfillment by Amazon (FBA) to ship products to your customers."