From a distanced perspective it looks equivalent to using a term for any disability as a jest term which on some level has the same level of offensiveness in most contexts. I think the intentions of most people are rather innocent and naive when using the word. It isn't spoken or heard as offensive in most cases.
People with mental retardation often understand that they have a mental disability. Sometimes they know and understand the term, retarded, and how it relates to themselves. I had a mentally disabled lady I used to ride with on the bus who would tell me the story each day of how her father held her head under water as a child which she explained resulted in her being retarded. She understood enough. I always wonder how the person with the disability would think/feel when they hear the term in jest. That's what matters.
The first man to raise a fist is the man who's run out of ideas. H.G. WELLS
The first principle is that you must not fool yourself, and you are the easiest person to fool. FEYNMAN If this is monkey pee, you're on your own.SCULLY
How would someone with cancer or MS feel about having their conditions hurled around as insults, especially with the implied character defects that the word "retard" has grown to have connected with it? Why should someone with a mental disability feel any different?
If the word retard is offensive, then so too should the words stupid, imbecile, moron, and idiot be.
Yes, there are individuals who happen to be mentally "challenged", but that is besides the point, which is that calling someone a retard, or retarded jokingly is funny.
I call myself retarded all the time whenever I do excessively stupid things like jump in the shower with my bra still on, or go nutsos searching for my keys which happen to be in my back jean pocket the whole time.
'Cause you can't handle me...
"A lie is a lie even if everyone believes it. The truth is the truth even if nobody believes it." - David Stevens
"That that is, is. That that is not, is not. Is that it? It is."
I don't really use the word 'retarded' in everyday conversation, but I have no problem with it. In fact, I think I would take more offense to someone who made it into some big issue than to someone who used the word offensively.