So about 1000 people have unfettered access to all of the live data, but there are absolutely no safeguards against them modifying it, copying it elsewhere, or peeking at it? That's terrifying. I'm under the impression that Google has more a stringent philosophy about this, and even then, one of the few SRE's that they do give broad access to was caught stalking teens via GMail data. Imagine the range of bad behavior an FB engineer can get away with after just 4 weeks of "Boot Camp".
Part of the reason I never made a real FB account was my general feeling in 2005 that securing a MySQL/PHP site against internal abuse takes incredible effort, and they wouldn't ever bother to do it. According to this article, that's likely true. And the "everybody can modify anything anytime" philosophy with little QA explains why, after 6 years, FB is still a gaping maw of security holes.