So its been pointed out that you can't delete posts but supposedly you can edit them. Well, I did once try to edit this post and the edit didn't go through.
There's a limited window for the average user to edit their posts. I'm not exactly sure how long, or if it changed when we went to Xenforo -- but it's around 15 minutes or so, I believe.
MartialTalk Meetup - Date determined (April 27-28)