Edit logs are already kept, though there's no web interface for viewing them, so it's not efficient. The notification could probably be more visible.

I haven't been keeping up with the new software, but the intention was for edit revisions to be visible to those who could edit the post (so OP, mods, admins, etc), though ideally it's customizable. Part of the problem with SMF was they had a very narrow view of what admins/mods/users should be able to do.