Hello Sean,

I have check your site and it seems like working as it should be. Here my screenshot: http://screencast.com/t/YdGHAkb7TfLl . Perhaps you are testing with registered user and admin in which admin can edit everyone comment. I have created 1 blog post and one user for this testing. You may delete the user after this issue is resolved.
Here is the code for displaying edit:

if( ($this->acl->rules->manage_comment || ($my->id == $comment->created_by && $this->acl->rules->edit_comment || $system->admin ) ) && $my->id != 0 )

Hope this will help.
Thanks.

It is totally not working properly. Please go to the comments that you posted. You will notice that I logged in as a 'registered' user from the front end and I was able to update both of your comments. In fact I can change EVERY word. This is nothing preventing me from totally changing the content of your comment even though I am NOT the one who created the comment. Check this problem out here: https://www.starch-smart.com/blog?view=entry&id=36

I have done this from the front end as a registered user and I also asked one of our other registered users to try it. We can both edit the comments of other registered users.

Actually look again at your screenshot. You will see that I added text to your comment before you took the screenshot. That is text that should not be there. :-)

I believe you are correct and that the problem was that I was in more then one group. Unfortunately one of our registered users told me he was able to click on the edit button to my comment and make edits. But, he did not save them, and, I think he must have been confused and must have been editing one of his comments. So sorry to waste your time on this one. If he is indeed able to edit somebody elses comments I will be shocked since I cannot now that I have changed the user permissions for Sean Carney to be Registered User only. :-)
Thanks, Sean Carney

Hello Sean,

You're welcome. Glad to hear your issue have been resolved.
If you have anymore question, please don't hesitate to ask us and please create a new ticket. I will mark this ticket as resolved.

Thanks again and have a wonderful day.