A lot of people on HN, myself included, consider votes to signal contribution to the discussion and not agreement/disagreement. Your comment is right in that they are often used as such, but I don't think it's desirable.
http://news.ycombinator.com/threads?id=pg
Discussions will end up quite boring if people use votes to agree or disagree rather than expressing their point of view in a reply. I tend to think of votes on HN similar to the options for moderation on Slashdot: vote up for insight, vote down for off-topic or flamebait.
pg from 1150 days ago:
http://news.ycombinator.com/item?id=117171
I have had this bookmarked for more than a year, as this issue comes up over and over and over again. Sometimes downvotes to express disagreement with the stated position in a comment is the most concise way, the way most friendly to other readers of HN, to indicate that the comment didn't add value to the community.
Of course, pg is experimenting right now to see if different software settings make upvotes, downvotes, flags, and so forth have better or worse effects on the community as a whole and on particular threads.
A link to his comment would be really appreciated. I find such statement, which is so contrary to guidelines, hard to believe with proof.
http://news.ycombinator.com/item?id=117171 "I think it's ok to use the up and down arrows to express agreement. Obviously the uparrows aren't only for applauding politeness, so it seems reasonable that the downarrows aren't only for booing rudeness." - pg, 1150 days ago
http://news.ycombinator.com/item?id=392347 "Downvoting has always been used to express disagreement." - pg, 852 days ago
http://news.ycombinator.com/item?id=658691 "IIRC we first had this conversation about a month after launch. Downvotes have always been used to express disagreement. Or more precisely, a negative score has: users seem not to downvote something they disagree with if it already has a sufficiently negative score." - pg, 665 days ago