I, personally, closed my account in January. I became wary of my personal outrage echo chamber. Every time I logged in my feed was just things or links to things pissed about or people's opinions on what they were pissed about. I felt like the good of feeling connected to folks that were, in reality, now strangers was being far outweighed by the pervasive negativity I was being subjected to.
I don't know how universal my experience is, but I walked away from FB feeling like I was part of a massive experiment gone wrong.