[clarkm]

Right now you can only do:

  keybase prove {twitter,github}

but more types are in the works. Though proving your identity on more than just your personal website has its advantages. For one, I don't know anything about your hosting situation or your security practices.

[niels_olson]

This seems very sensible. For example, at a key-signing party, as I understand it, ideally everyone knows someone there, or can authenticate via two separate government ID. The benefit here is that keybase.io has removed "government" from the equation.