Back in October of 2010, the US Patent and Trademark Office and the European Patent Office announced the launch of a joint program designed to harmonize their patent classification systems.
This program, referred to as the Cooperative Patent Classification Project (CPC), will create a single classification system based on the International Patent Classification scheme administered by WIPO and to be used by both offices. Once operational, this new system should greatly improve patent searches and examinations by eliminating or reducing classification disparities between similar inventions.
With so many applicants seeking patent protection outside their home country, this initiative (like the PPH) aims to foster cooperation and streamline examination between the USPTO and the EPO. Subsequent goals include expanding participation to other patent offices and use by the public.
Currently, the CPC Program is scheduled to go into effect in January of 2013. Further information on the CPC Program can be found here.