It is not improbable that a separate charge is lodged against Mark Karpeles and be extradited, being single owner of Mutum Sigillum LLC, based in Delaware.
Isn't Mark attending bitcoin2013 ? It's located in the US, so that would be a good time to arrest him wouldn't it? Not that Japan wouldn't extradite him. But this sounds like a good opportunity to bring him to "justice" quickly.
I really really hope Mark never visits the US. But who knows.
It would be very foolish for Mark to attend said conference. But then again, the man is a FOOL.