This is SO huge. And Facebook gets the biggest of big ups for this, and 1 of 2 things will happen because of it:
1) Lives will be saved based off of suicidal posts that people toss up on their statuses when they're either thinking about, or about to harm themselves.
2) People will post something up like that to get attention, have it automatically reported by the AI, get in trouble for faking their suicidal thoughts, and Facebook may get a lot less dramatic.
But really, HUGE shout to Facebook for trying to stay ahead of the self-harm epidemic and get people help, whether they realize they need it or not.