One of the improvements made by the AIA is the ability to requset Supplemental Examiantion to cure defects in a patent.  Since September 2012, only eleven such requests has been filed as illustrated in this graph from the U.S. Patent and Trademark Office:

On January 25, 2012, the U.S. Patent and Trademark Office published proposed regulations for the new Supplemental Examiation, which takes effect on September 16, 2012.  These proposed regulations can be found at Federal Register Volume 77, Number 16: http://www.gpo.gov/fdsys/pkg/FR-2012-01-25/html/2012-1480.htm