Re: I don't fully understand this
What he's trying to say is that MCX members won't pay payment processing fees because MCX will BE a payment processor. However, being owned by its members, they won't pay transaction fees. They'll probably pay some sort of largish yearly membership fee that pays for its operation, which will keep it restricted to only large retailers.
I wouldn't look for fraud prevention to be high on their priority list, since they'll be drawing directly from people's bank accounts they have little incentive to care. It'll be your problem, not theirs.