I'll tell you what it takes to keep Apple's secrets...lawyers, lots of lawyers.
As a former Apple employee, I know just how seriously Apple takes its secrets. Even today, years after my NDA has expired, I'm reluctant to talk about things that Apple flagged as confidential. One reason for that reluctance is because of the respect I have for the company and my friends who still work there, but of course another part of it is I don't want to make anybody there angry.