[symlinkk]

HIBP is simply a database of email addresses that have been associated with leaks. I don't see how that would help him identify private keys.

[johncolanduoni]

Well AFAIK Twitter doesn't give users keypairs, so I think they meant do the same with leaked credentials.

[jasonallen]

yeah, that's what I mean. Provide a service that reports back leaked working credentials so that the service provider can lock down the account.