Number one rule, practice self control: don't reply to list unless it's important for everyone to know,not just that you want them to know it ;-) Otherwise, reply to individual poster or not at all. Of course this applies more to the more assertive posters.
However, if one is generally reluctant to post, thinking one's contributions are not important enough, one should not be discouraged by this. And the fact there is less gratuitous posting may mean more reluctant posters feel more free to post.
Also self-control cuts down on eventual debate on what should or should not have been moderated.
Carol in dc