SHA3 IANA registration - method?

[Phil Pennock]

Sorry for asking here, but mail to <ietf-openpgp-request at imc.org> is
bouncing, so it looks as though the ietf-openpgp list is now completely
dead.  The only IETF forum I can spot is the concluded openpgp WG:
  http://www.ietf.org/wg/concluded/openpgp.html

So: what's the best mechanism for registering a "Hash Algorithms" entry
in http://www.iana.org/assignments/pgp-parameters/pgp-parameters.xml for
SHA-3 ?  RFC without implementation or implementation based on PRIVATE
USE code-points and then RFC?

I'm guessing that a working implementation using a PRIVATE USE
code-point, per RFC4880 section 13.10, is a decent way to go?  Or is PGP
one of the protocols where folks have settled on avoiding private use
fields because of the difficulty in migrating away from them?

Does anyone know of someone already writing the necessary RFC for the
IETF Consensus mechanism?

Thanks,
-Phil