who cares what form of authentication is used, since history told us that for each law applied there will be a way to avoid it. The biggest problem is why do they need OUR personal details like retina, finger prints, dna or whatever is strictly bound to us. Is always said "we wont use it for "x" reason , is just for your security" .I would never trust to give those details to anyone , and certainly i would not accept to be chiped like a cow.Now sounds promising all these technology that are safer and easier to use but in time there is a huge chance that you wont have a private identity.I strongly belive that for now, the safer way to encrypt your personal data is a password that is wisely choosed. Like some said earlier , all form of authentication are digitally stored, so any of these at some point they can be cracked, so again , why the need of my fingerprint , retina scan .......