I do think it would be a good idea to have some kind of mass edit mode for the posts, so I can have checkboxes to disable/enable "Allow comments" and "Allow pings" and then save those posts that are checked for update. Because entering each post, disable comments/pings and submit the "whole" post (with post data, title and so on) just to change couple of settings, isn't very efficient.
I'm also not sure if ping-o-matic will receive a ping from me on these edit changes? Is that needed when I just want to change the allow settings?
Maybe I'll try to make a mod :P But don't hold on your breath.