Twentieth Century Fox are doing their best to keep a tight lid on the plot for summer 2013 release The Wolverine. What we do know, however, is that the film will be set in Japan and based on the run of comics by Chris Claremont and Frank Miller, and new casting news might give fans of the comics a clue as what the storyline will be.
According to a report by SuperHeroHype, the new actors to join the cast are newcomers Tao Okamoto as Mariko Yashida and Rila Fukushima as Yukio. There have also been two male characters cast: Hiroyuki Sanada (Sunshine, Rush Hour 3, Lost) as Wolverine's foe Shingen, and Hal Yamanouchi (The Life Aquatic With Steve Zissou, The Way Back) as a character called "Yashida". It's unclear which of the Yashidas this refers to, since the most likely candidate would be the already-cast Lord Shingen, leader of the Yashida clan.
Presumably further details will arise before long, but "authenticity in ethnicity" casting fans will be pleased that Fox are making the most of Japanese talent for the film.