I first encountered the word 'retarded' in really bad books, I remember seeing the phrase 'retarded Spring' to refer to a long winter. Then it popped up in French "Je regrette d'arriver en retard, Madame." so it just never seemed to be a word with particularly bad connotations.

I still can't get that worked up about it, possibly because I've worked with children and have had a fresh reminder of the charming words they use when they WANT to be offensive to the intellectually disabled - I'd rather be called a retard than a flid, window-licker or special (pronounced SHPESH-ULLLLLLL)