I'm also curious as to what the mean (or median) HN political viewpoint would be, and which is the majority/minority viewpoint.

Personally, I tend towards liberal politics. I interperent this statement as "Liberal politics dominates HN, and conservative politics is a minority that gets downvoted"

Even assuming that's accurate, I tend to find more conservative viewpoints on this forum, compared to other forums I browse, and I find those conservative viewpoints better argued, and more likely to affect my view.