They did, several months ago. Scratching my head a bit...
Colonel, USAFR
In accordance with the 2005 Base Realignment and Closure recommendations, an Office of Integration (OI) was formed in November 2005 to oversee the merger of the Walter Reed Army Medical Center (WRAMC) and the National Naval Medical Center (NNMC). That merged facility will be staffed by Army, Navy, and Air Force medical personnel and will be the core of an integrated military medicine system in the National Capital Region (NCR). What in 2005 were three medical centers, a small community hospital, and 19 clinics offering medical care to military beneficiaries in the NCR will become, with oversight of the OI, a single tri-service medical center, a large tri-service hospital in Northern Virginia, and 20 area clinics
Groundbreaking took place on July 3, 2008 with President George W. Bush officiating.
http://en.wikipedia.org/wiki/Walter_Reed_National_Military_Medical_Center