I have always held that the "appropriateness" or "vulgarity" of language is inextricably tied to the context and intent of the user.
While, if I say "F*** you", that is without question offensive, and intentionally so, but would I be offended if my wife grabbed the back of my head and said "F*** me"? um... NO!
I have been known to have words with the punk in the car next to me who is playing his rap music so loudly that the MFers and F's and othe vulgarities can be clearly heard by my 10 year old daughter in the back seat. I think I have the right not to have a jaunt to the ice cream store interrupted by such crap. The problem with that, though, is unless the police witness the offense, it is nearly unstoppable. And, if I get into a fight with the punk ass, then, best case, my daughter sees a bad way to handle disputes, worst case, I go to jail.
stupid rap music.