They shouldn't be banning it, one of the best places to get new investors for your coin is through facebook, there is a large reach of people there and it is a perfect place for new cryptocurrencies. What they should do is to impose more rules but out right banning it isn't advisable. They have not banned it yet and I don't think that they will ban it.
Really? If its true its a big loss for them, bitcoin right is on of its success and that us probably the stupidest decision that facebook will made, banning bitcoin, crazy, they will lose large amount of money if they do that, because bitcoin rightnow is very famous