Anybody who reads the signature line can see my real name anyway. Aussies have always used nicknames as ID so why are we worried about having fifteen people with the same name, and an initial behind it to identify ourselves.
When it comes to it, getting the right person to send a message to we end up looking through a group of peoples names and think which one has the correct last initial, instead of a nickname that ID us individually. I would personally prefer to see in the members list, our names beside your "Forum Name" so you can address the issue you talked about Beatup, and everybody stays individual on the Forum.
My .02c worth.