Payments tying device and authenticated consumer to retailer ID is a potentially disruptive market. Facebook has capital and resources to build out own network, but that is way too much work to leverage their social platform. I believe David Marcus. This is the most likely path Facebook will take. Though I'm sure somebody would be up to this task. It's very doable for much less funding than Square or even Clinkle (25M). There are also several ways to accomplish this. If you are up for this, let me know and I'd entertain assisting to do so. See GetCard1 for my latest.