"The main changes made by the interim rule and adopted by the final rule include: prohibiting employers from accepting expired documents; revising the list of acceptable documents by removing outdated documents and making technical amendments; and adding documentation applicable to certain citizens of the Federated States of Micronesia and the Republic of the Marshall Islands."
Also see a USCIS Q & A that provides clarification on what the final rule accomplishes, how and when it will affect employers and employees, and where to find detailed information on the public comments to the 2009 interim rule.