They aren't going to move over; the reddit/twitter model of 'crosspollination' is fundamentally flawed - if trolls can just stroll over from their little trollzone at any time they will do so and every conversation will get derailed with politics/gender/whatever gets the most engagement; character assassination will be the dominant paradigm.
Silos are the answer. Open to all but topic focussed and with no cross-referencable userhistory. Or 100% anonymity with no userhistory i.e. futaba type message boards.
