[dfc]

I cant understand anything that you wrote. Yes you can distribute keys in a blockchain. After Alice grabs a key out of the blockchain how does she know it is Bob's key and not Eve's?

[Rhapso]

This is a better summary then I can hack together: http://namecoin.info/

I have issues with their implementation, but in general the message is right.

[dfc]

How does Alice attest to Carol's key so that Bob (who trusts Alice) can identify/use Carol's key for communication?

[Rhapso]

Alice just signs Carols name. Bob looks up Carol's name in the blockchain. The primary application is TLS style authentication, so the user ideally already knows the name of their intended recipient.