I found the title of this thread offensive and read the thread out of curiosity. I was pleased to see that most of the posters (all that I read) kept a scholarly stance and not a bigoted one.
I do find the N word very offensive no matter who says it. There is something very ugly about that word that surpasses all other words.
I recall hearing it on the playground when I was a school teacher and trying to explain to the children who used it that, "I'd rather hear the F word than that one."
I have enjoyed Richard Pryor's acting, but couldn't listen to his stand-up routines because of his use of that word.

While I don't like hearing other people insulting their race, religion, sex or sexual orientation, somehow the N word has a particularly ugly, hateful feel that, to me, cannot be matched by any other.