[Mailman-Developers] status of backscatter prevention?

I remember a number of threads about backscatter prevention, but I
don't remember the result. Perusing the archives isn't much more
enlightening. Where are we on this?

In particular, other than removing all but one of the aliases, have
we made it easier for people to run a backscatter proof list?
Meaning that all subscribe, unsubscribe, etc are done on the web ui
and nothing in the server automatically responds to e-mail other than
legitimate list mail sent by subscribers?

I also remember discussions about honoring SpamAssassin headers to
detect spam. Status of this?

-- Jo Rhett Net Consonance : consonant endings by net philanthropy, open source
and other randomness