1. As part of the Draft Standard version of MIME.
2. As a separate little RFC.
3. As part of the netnews RFC revision.
I don't intend to try to speak for IESG on this, but, based on what has
happened in the past...
-- The SMTP extensions that authorize/provide for 8bit transport are
running one standards track position behind MIME, i.e., we can expect
them to go into "proposed" on roughly the same time frame that MIME
would ordinarily enter "draft".
-- It is going to be very difficult to write a coherent explanation of
how to handle quoted 8bit in MIME without reference to some Internet-
legitimate way of transporting it, i.e., without reference to the SMTP
Extensions "service extensions" and "8bit MIME transport" docs.
-- I think that the combination of the above suggests that #1 is
equivalent to "hold MIME at pre-draft-standard and wait for the SMTP
extensions stuff to catch up". Even if it did not, adding this now
would imply inserting a new piece of protocol into the MIME spec for
which there would be no, or only a very short period of, implementation
experience. That, too, would imply holding up the works. I doubt that
there is anyone who would argue that "hold up the works" is desirable.
-- Unless the "netnews RFC revision" is headed toward standards-trace,
rather than a separate (non-IETF WG) collective effort, specifying this
form there is only slightly better than the x-quoted-8bit plan, and may
or may not meet the requirements for proper registration.
I think that leaves us with #2, assuming those three are, in fact, the
only reasonable options.
john