If Apple does not want their devices to be used as intended until an embargo date has passed they should keep them on premises. Once the device is out of the gates the secret is out as well. NDA's are very effective when you are talking about documents and adults. As soon as you're talking about devices and/or kids NDA's are ineffective because anybody that spots the device can post a picture without any recourse by…
This all happened on Apple's campus, mentioned in the second paragraph. Maybe read the article before commenting?