I hope you're aware this isn't like someone calling you fat during recess in the second grade... "Tranny" is often accompanied by violence. One of my best friends is TG, she has had a fairly easy transition but friends in her circle have been raped, severely beaten and abandoned by their families. When you spend 10 years hearing the word "Tranny" in a negative context such as, "You tranny faggot", it becomes more than "just a word". If you're a straight WASP I will understand, but if you're gay, black, hispanic or anything else just imagine trying to "laugh it off" while your head is getting stomped on.
To the people complaining that others are "oversensitive" it's a fucking word with a dozen alternatives, if you can't even expell a SINGLE WORD from your vocabulary to make others feel more respected and safe, you're a bad person. Just say "TG" if you need a short version. It's blowing my mind that this thread is xx pages and people are still defending their right to say a word when they know it hurts other people. I expected more from this community...