Either it was there since day 1, together with Facebook and some others, or your blacklist is a pointless show.

What nobody started discussing so far: Every user actively pushed these shady sites. They are/were all active parts of the problem. And usually they somehow knew it. They'll come with lame excuses, as if the issue ever was a technical one, and too difficult to get, but in fact, no, things cannot be more obvious. To everyone who ever got in touch with other human beings. It never was a tech problem.

I'm excited when this discussion will start. But we are far away from it yet.