Chiggmo you're right that the intent behind the words is the most important thing. But there is a lot of habitual use of a word like "retard" where the person using it just has no clear idea of the intent that might be taken. Much of this thread has been about clarifying that, and trying to promote some understanding, rather than making a case for censorship.
And forget about any particular word - there is no room here for any kind of behavior that is purposefully derogatory. That goes to something as casual as calling people idiots for some point they have made which you dislike. It's unnecessary and only weakens any opposing argument, and most importantly, usually leads to a stupid pissing contest. So, if you were to blurt out something about what I said as being fucking retarded, I would not hold you in some completely low regard due to using that word, being able to understand that it was just blurted out. But I would draw attention to how the word can be taken, even if not intended, and most importantly, draw attention to the need to stay away from the actual intent of needlessly disrespecting any posters here, no matter what the words used may be.