Bloodyelbow.com has the scoop from an army official:
According to military sources speaking exclusively to BloodyElbow.com, the Department of the Army has not yet approved the Ultimate Fighting Championship event titled, “Fight for the Troops” set to take place in Fort Bragg, NC on December 10th. It is not clear whether official command at Fort Bragg has approved the event either.
UFC President Dana White said on live national television during the broadcast of UFC Fight Night 15 that the event would take place at Fort Bragg and would send proceeds to the Intrepid Fallen Heroes Fund. The UFC has staged an event on a military base. On December 13th, 2006 the UFC held UFC Fight Night 7 at Marine Corps Air Station Miramar in San Diego, California.