Resolve the Great Reply-To Debate once and for all, by making Reply-To munging a per-subscriber preference.  That is, Mailman would allow each subscriber to control whether, for each post that subscriber receives, Mailman sets Reply-to to the list or leaves Reply-to untouched.  The default would be "untouched".

The usual references on this topic:

• http://www.unicom.com/pw/reply-to-harmful.html

• http://marc.merlins.org/netrants/reply-to-useful.html

• http://marc.merlins.org/netrants/listreplyto.html