Elizabeth Bear is a writer of SF and fantasy who has umm more than one attitide problem. (See mike's comment below.) She wrote a post last winter about how to write chracters of colour. Someone said 'For someone who freely hands out advice on the subject you don't do it all that well yourself' and cited one of her works. Bear was all gracious 'I'm so sorry the book didn't work for you.' Her friends were not gracious in the least, and responded with a barrage of hysteria, gratuitous insults and four letter words. Bear's last word was 'In my initial response I was trying to present an example of how an author deals with criticism from POC but forget that, I've had it, being nice gets you nowhere.'

The whole thing is now famous as Racefail and the dryest account (recommended for blood pressure) is here (http://wiki.feministsf.net/index.php?title=RaceFail_09). Let us say that the reputations of several Big Names in SFF were undone by their behaviour during this.