[jVinc]

Personally I would say that the downvote features is extremely useful and valuable. Especially on Hackernews, as it helps to protect the community standards which are quite different from for instance reddit or other tech discussion sites. You very rarely see anything like blatant flamebate, trolling or flamewars, because they quickly get downvoted and grayed out, and are generally ignored instead of going to the top of a thread because "controversy increases engagement".

[mihaitodor]

It's driven by the top x% of the users, though, who I'd guess are not that many (maybe 1%?). This makes me think that HN managed to select a healthy moderator community, but I doubt that the downvote feature was the main driver for that.