Last 22th of March, the Access Board released the new 508 draft. It provides requirements for electronic and information technology, necessary to implement the requirements for Federal departments and agencies (“Agencies”), including the United States Postal Service, set forth in section 508 of the Rehabilitation Act of 1973, as amended (29 U.S.C. 794d).

You can find further info in http://www.access-board.gov/sec508/refresh/draft-rule.htm

I would like to point out the "Amendments to the ADA Accessibility Guidelines", item "220 Automatic Teller Machines, Fare Machines, and Self-Service Machines" which is very interesting and extend the existing regulatory framework in USA. http://www.access-board.gov/sec508/refresh/draft-rule.htm#a220