I would note that anonymous accounts must comply with the Twitter rules. There are no exceptions for them. If they make a hateful comment, they are subject to the Twitter rules. Of course it is a delicate balance, but at this time we allow anonymity and will continue to allow it.
From a personal perspective, I've had a number of women's groups come to me in Canada, but also my Korean colleagues, to say that the conversation for them is entirely different because they are allowed to be anonymous and they are allowed to have conversations that they are fearful to have face to face.
While we recognize certainly the problem we see in probably Canada and the United States with anonymous comments, we are sensitive to those who are coming to Twitter to have their voices heard in ways that they couldn't be heard in other locations.