Yeah. I remember a lot of complaining when Ken Watanabe was cast. I was kind of surprised he took the part, because it was so small, but it ended up working out well for him: Batman Begins
was a hit, and his status was boosted (more people knew about him) and Nolan eventually ended up working with him again in a much larger part for Inception
It's actually kind of funny, because Nolan re-hired two of the villains of Begins
, decoy Ra's (Watanabe) and the Scarecrow (Cillian Murphy), and in Begins
they didn't have any scenes together, but they did in Inception
. Plus, Tom Hardy is playing a villain in The Dark Knight Rises
-- Nolan definitely has a penchant for re-using actors in his movies, especially those that play the villain.