1: I quit fb because the culture in the team I was on was toxic as fuck. Backbiting, backstabbing and oneupmanship. Ain't got no time for that. Fb does not need you and everyone makes it very known.
2: Dunno, dont read about FB since I gives no fucks about them.
3: The team I was on was stagnant as fuck. Lots of bragging but little showing.
4: Probably if you want to put the effort in to get noticed.
5: Cant say for sure, the question is largely subjective.
6: Definitely feels like a large bloated company to me.
7: Lots of politics. Blahhhh.
8: I work for a consulting company now. Much more freedom. Every project has huge impact and I make about 45% more than I made at FB with potential to accelerate my compensation by delivering sooner than deadlines.
TL:DR Fuck FB.
edit -- I worked at FB for two years.