The author writes:

"The borderless nature of the web means it can be hard to avoid the ranting bigots and creeps we would ordinarily shun in the real world."

While I understand his point, I believe this is one of the great things about online communities. I think many people are too quick to shun those who we disagree with (I know I'm guilty of this). I think there can be a lot to learn from those we vehemently disagree with.