B) Everyone's already acting like the sky is bleeding falling with these diplomatic cables, so you can imagine the same will happen with a leak on the banks.
C) Continuously saying "How?" is not a valid defensive argument.
2nd point: It's like a controlled forest fire. If you carefully maintain it and promote stability, nature can run its course without causing more of an impact to people than it should. If instead, you simply sit back and let it burn chaotically, then it's going to cause a lot of unneccessary damage to innocent people. Perhaps it's not the best metaphor, but it's the best I can come up with at the moment. Yes, no matter what you do, people are going to get hurt, but they'll be hurt a heck of a lot less if you manage the event properly.
Devil's Advocate to be sure, but considering the goal of this is transparancy, it would mean a lot more if the bank would come clean itself, rather than wait for a third party who claims to have them already beaten.