The Web was social long before "social media" and "social networks" showed up, and it will remain social for the simple reason that it is universal. Emphasis on the uni. There is only one of it, and it was designed to connect everything on it, without favor. All attempts to replace the Web, no matter how popular at the moment, will fail if they don't respect the Web's full nature.
If silo-builders like Zuck thought about what they could do for the Web, rather than what it could do for them, where would they and the rest of us be today? Answer: it doesn't matter.
What matter is adding value to the Web itself, because its nature is NEA:
The tide is turning. We can feel it. Whatever we call it (e.g. "next Web," "3.0"), it will be the real thing only if we improve what it was in the first place. IMHO, anyway.