I think the biggest problem is authorization, you don't want random people on the Internet to be able to see your family photos. That's what Facebook solves. We

I think the biggest problem is authorization, you don't want random people on the Internet to be able to see your family photos. That's what Facebook solves. We need a decentralized ID system, something like a private/public key, that is easy to implement and even easier to use/login to a site with.