I think it's more the case that members of the HN community who are likely to vote at all on a certain comment tend toward certain common views. For example, a

I think it's more the case that members of the HN community who are likely to vote at all on a certain comment tend toward certain common views. For example, a comment about Google is more likely to be voted on by Google employees and Google fans. A typical user wouldn't vote at all. If that comment is negative about Google, those who care about Google are more likely to vote it down. I suspect this applies to all sorts of subjects, it's just more visible with something as easily identified as a "Google comment" or an "Apple comment".