A question to you MT - are you using your own key/validationserver?
I've gotten a couple of questions if It's possible to use the same key for both Bit LC and MTGox - and it all depends on if you're using yubicloud or not.

In either way - the MTGox-keys are based upon YubiKey 2.2 if i see correctly - which supports double identities - so it should not be a issue anyway.

I think MtGox use their own validation server and not the YubiCloud. John.