[vidarh]

You would not be able to stop individual users from doing so, but you could potentially make it legally untenable for commercial/corporate operators.

But personally, regardless of legality, if Google implements this with the degree of disclosure of e-mail details, I'll find another operator that isn't implementing this proposal.

[magicalist]

The whole point is ease of key exchange. Of course if you don't want any hint of your email details out in the world you shouldn't use it.

[vidarh]

Ease of key exchange does not justify publishing what is effectively a public ledger of who I start communicating with when.

[magicalist]

I think you're misunderstanding the gossip protocol, but, regardless, that was not the claim I was responding to, it was that the disclosure of email addresses (or a hash of them) with no way to remove them from the Key Directory is somehow beyond the pale for a public (and automated) key exchange system.