although 51%+ is a pivitol point. remember its not the fact that they have 51%, its the fact of if they will do anything nasty once they have 51%+
although id like to think they wouldnt shoot themselves in the foot by doing anything... thus nothing will change, there is that chance that the owner of Ghash is a complete knob and would do something.. so dont think of the 51%, think about if GHash CEO is a knob or not. and lets hope he is not.
with that said lets get all your miners on different pools to disburse the hash-power so we never have to find out if Ghash CEO will be a knob or not