I don't think that one was ever "acceptable". That being said, literally every term after/including "African-American" in that list is socially acceptable. Not sure what they're going on about.
>>dmonit+(OP)
I'm not so sure. It sure gets used a lot in "Huckleberry Finn", even by people who aren't being malicious. (From my recollection, anyway. It's been ages since I read it.)