In case you can't get your head around it: iPhone SDK is _not_ available to the public. Everyone who clicks on "I agree" is _not_ the public anymore, but someone who has agreed to the NDA. Apple invites everyone above the age of 18 to join the club; that doesn't mean every member of the public is member of the club.
Ask yourself this: If a gazillion programmers employed by Microsoft and Nokia download the SDK, and copy everything they find into their own products, what will Apple do? Sue them for every penny these companies got. If these same programmers read something on the publicly available MacRumors page, and copy it into their own products, what can Apple do? Nothing.
According to you then Mac programmers should never be allowed to talk about anything because someone else may incorporate the ideas.....
So therefore, by that logic we shouldn't be allowed to talk about Leopard programming either because Microsoft could take ideas from that. After all, in order to join the club of Leopard programmers you have to click an "I agree" button.
Have you actually bothered reading the agreement? I have. It mentions nothing about not being allowed to discuss issues with the SDK itself or even features. You don't have to sign a thing to get access to the WWDC videos about the SDK. There are other types of intellectual property laws that cover copying ideas, NDAs are not it. Not to mention the dubious legal position that EULAs have to begin with, and no court in the land would hold up that you cannot talk about a program that is available to anyone, legally, for free, in the world.
You are obviously not a lawyer and are contributing nothing to the conversations other than spreading FUD. I kindly ask that if you have nothing to say, please stop spreading NDA nonsense. Its annoying and just plain wrong.
If you feel I am in error, please cite SPECIFIC parts of the EULA that prevent programmers from giving advice to each other, otherwise please keep quiet.