I think it's people who disagree with what the person is saying, but if the person has completely valid points, then why give the comment a negative vote? I've seen more than a handful of comments which were voted -1, which I saw absolutely nothing wrong with, and would generally vote +1 just to even it out.
Also, how can we get people to chill out more in the comments section? It reminds me of a comments section on news.com.au or digg, full of hot-headed people who use the internet to vent their anger. Hopefully OzB can continue being the great, reliable service it has been ever since I started lurking. I just don't want people, including myself, to be put off by the antics in the comments section. Yeah, I know, you can skip past them, and that's what the voting is for, but really, you never used to have to skip any comments. Most were well thought out, and contributed in some way to me, the reader, understanding the bargain a little better.
Think about it.
(Mod — moved to Announcement/Feedback forum)
Do you think we should list out the users who have voted on comments to introduce a bit of responsibility?