Our nations new Chairman of the Joint Chiefs of Staff is Navy Admiral Mike Mullen.  The U.S. Senate on Friday confirmed Mullen as the president's top military adviser, replacing Marine Gen. Peter Pace as chairman of the Joint Chiefs of Staff.  Pace was not asked by the Bush administration to serve another term as head of the Joint Chiefs of Staff because of his role in the Iraq war. Politicians and retired generals have blamed Pace for not properly planning a post-invasion program for Iraq and for using too few troops. To put it in simple terms, General Pace is "so fired."

You can read Mullen's bio here

The responsibility of the Chairman, once held by my favorite general, Collin Powell, is formidable.  You can learn more about this position at wikipedia