I'm happy to elaborate on nearly any aspect of Hacker News, but this is one area (maybe the only area?) where I resist the impulse to explain. We're in something of an arms race against a lot of people who try to get their content on the front page through non-organic means. Accidentally helping them do so would be a genuine shot in the foot.

But let's say what good voting means to HN. It means voting for something that you personally find intellectually interesting, regardless of who posted it and regardless of what you or your friends are hoping to promote.