As a Syrian who have used many throw-away accounts on FB, this is a life or death matter for many of us. I'm sure the Syrian regime will use this information to track activists. I have checked and there are 7 million leaked accounts from Syria, probably covers everyone who uses Facebook in the country. Facebook made it mandatory to provide the phone number and now that this is leaked, they bear the moral responsibility for all the people who will be affected by this.
> they bear the moral responsibility for all the people who will be affected by this
Facebook should not be held responsible for dictatorships and totalitarian regimes killing people - even if they use Facebook's leaked data to do so. It's quite unfortunate, but the responsible party to blame is still the people actually doing the killing.