while MS has been trying to keep the lid on this jar airtight as you said, 90% of the time, there is always some way to get around it (not that i want it to be leaked though), the question is if someone will be able to find that way and then actually start sharing it.
i can understand them having tight security for the SDK, but i could imagine them leaving a hole somewhere in the consoles security. they cannot deny that with the xbox being fully hacked, it brought them alot more sales. they are a business after all and in the end, all businesses are in it for the money, but they do have to protect the interests of investors and developers too