While there is little doubt there are sock-puppets among the active users, in some parts of the world Facebook is the means to interact with each other. There are regions where Facebook has usurped the internet on which it runs to such a degree that if an organisation hasn't got a Facebook page, they might as well not have an internet presence at all.
But while Facebook keeps pushing for total market saturation, there are scant markets yet unexplored. Add to that the decline in use among certain demographics and one has to ask:
When will the world have reached peak Facebook?
For the purposes of this question we’ll look at the Monthly Active Users (MAU) Facebook usually reports with their quarterly earnings to determine stagnation. This question resolves positive if over the course of a year (4 quarters) Facebook reports an increase of 8 million MAU or less. If FB stops reporting MAU, or changes the methodology with which they determine these, the question will resolve ambiguously.