It seems the problem is scaling up production to an industrial scale.
Nothing in the article made me believe new graphene membranes are just around the corner. Beyond manufacturing cost, there are number of other "what if's" that still need to be answered.
How quickly will they become plugged up? How will the sandwich material required to keep them in shape hold up? Will they be cheaper? Will they last longer? Will they require lower pressure?
I'd love to see a cheaper, easier to maintain watermaker. I'm not holding my breath.