What about something like ErMaC did earlier.. tried to post a pic from another site (something-awful.com) and instead got a HUGE pic of a ... ahem.. head... squirting.
Needless to say, it's best to have an edit button to get rid of stuff like that on your own instead of having to wait for a mod or Phade himself to remove it.
I visit a lot of bulliten boards on the net, and this is the ONLY one where there is no edit button.
The ONLY negative thing that happens when there is an edit button is that you can change what you';ve said in an argument to make someone look stupid.. and that's fine because they cna do the same thing. And if you really want to participate in that kind of immature behavior, I'm sure the mods have a nice big boot to ram up your ass if you don't stop
In other words, there are not really any negatives about having an edit button!