NDA covers anything and everything about it. You don't sign papers making it illegal for you to even acknowledge something exists, and then say it exists. Especially publicly.
I don't know on which podcast I heard this. But it was some developer talking about MOVE and when they heard for first time about it from Sony. It was way before release of course but I remember mostly him saying that they had to sign 15 (or some other ridiculous number) papers/NDA before they got it.