Michiko Kakutani wrote a marvelous slam about the latest attempt to force Mark Twain to write according to some people's taste; "New 'Huckleberry Finn' Edition Does Disservice to a Classic", New York Times, 2011-01-06.
One of her best sentences on changing "nigger" to "slave" was, "Never mind that attaching the epithet slave to the character Jim — who has run away in a bid for freedom — effectively labels him as property, as the very thing he is trying to escape." Another is that it "stands as a powerful indictment of slavery (with Nigger Jim its most noble character)".
Rewriting by translators is one reason that I prefer reading books or seeing movies in the original language. I may comprehend the text less in the original, but that is my doing, not some intermediary's.
See also "Bowdlerization", Melvyn Magree, Reader Weekly, 2001-04-12.