It just shows some people inside think that outsiders are too stupid to understand/appretiate what the insiders are talking about, so it better stay hidden. Some of the employees' comments also betray this belief.

Why couldn't a discussion about the future (features? :)) of Facebook could not be open if it's such a big and far reaching platform? What's to hide?

Media would have hard time feeding on it, compared to the current situation where it is all interesting and whatever because some "secret" "leaked" and therefore it is "newsworthy".