It's an attempt to solve the key distribution problem. By having you verify your keys on third party sites, a MITM or NSL attack (providing you with fake keys so your messages can be intercepted) gets a lot harder as you have to attack n sites simultaneously instead of one.
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Have you seen https://keybase.io/ that's an ideal place for your GPG keys (and more) :-)
I can't tell if it's finished yet:
Nor do I understand why I'd use it. Do lots of people post GPG encrypted messages to each other on gist?
It's an attempt to solve the key distribution problem. By having you verify your keys on third party sites, a MITM or NSL attack (providing you with fake keys so your messages can be intercepted) gets a lot harder as you have to attack n sites simultaneously instead of one.