And this is just my opinion...

I think since moderators are simply members wearing different hats, they should have separate member log-ins and moderator log-ins. The moderator names should be made public, but which moderator name corresponds to which member name should be kept secret. I further think edits, deletions and closures should be "signed" by the mod who does them using his/her moderator name. Whether or not moderators would choose to accept PMs sent to them under their moderator names would be strictly up to them.

This would go a long way toward eliminating some of the "Orwellian" overtones of total moderator anonymity while providing enough anonymity to allow the moderators to do their jobs without being continually assaulted by irate PMs.