According to this recent Mainichi article (Japanese) and this Bloomberg/Businessweek article (English), Ambassador Ichiro Fujisaki will be leaving his post at the Japanese Embassy in Washington, D.C. His successor is reported to be Kenichiro Sasae, the current Vice Minister for Foreign Affairs. Also, Shinichi Nishimiya, the former Ambassador in New York until 2010, will be the new Ambassador to China.
Here’s the link to the Japanese article in the Mainichi: http://mainichi.jp/select/news/20120820k0000m010095000c.html
Here’s the link to a Bloomberg/Businessweek article in English: http://www.businessweek.com/news/2012-08-19/japan-to-replace-envoys-to-u-dot-s-dot-s-dot-korea-yomiuri-says
Read an exclusive interview JQ magazine conducted with Ambassador Fujisaki at the 2010 JETAA National Conference: http://jetaany.org/magazine_files/JQ_SeptemberOctober2010.pdf