Seems to me like Namecoin is a practical, secure method of distributed identification and verification. It's basically a secure P2P key:value store based off of Bitcoin's method of operation. Its original intent was to replace DNS (the website name is the key, the IP address is the value), but I see no reason why we couldn't also use it to host public keys.
Nothing. The same way you can go buy iamthebankofamerica.com for a couple bucks and put all the keys you like on it. But once you go to the actual Bank of America domain record you'll get back the real certificates.
