@BlueNile I had that on, foolishly thinking that people would not abuse it (which was one of the reasons that it was off in the previous forum installation).
Sadly within this short period of time people did abuse it, deleting content that was valuable. I had to undelete those posts and change the poster name so that people won't miss it. Either way though, there is a full log on what has been posted so even if there is an edit we can tell (admins only) what has been edited from/to and when. This allows us to resolve disputes if they arise.