[TomOfTTB]

As someone who I'd like to think has proven to be of some worth to the community I can tell you first hand that people downvote based on disagreement all the time. In my experience it's just a few jerks (I've never been significantly down voted on a quality comment) but it does happen.

I think there was even an "Ask HN" topic on this a while back with people defending the fact that they downvote because the disagree (Sorry, not enough time to search for it right now)

Oh, and I agree completely about the article.