J. Michael Diehl writes:

This is a good point, but I believe that eventually, people will want to sign legal documents via pgp and such. So being able to tie a pseudonym to a reputation to a public key to a REAL LIVE PERSON is very important. I think

That is a good point too. Perhaps the laws and practices of Notary Publics may serve for one degree of assurance. They commonly need to know who is asking them to notarize something such as a will. I don't remember how they do this. I suppose that a Notary public should have a published public key that she uses like her seal.