When browsing the titles of Hacker News, I look at the vote and comment count to determine whether an article is high quality or not. I am not sure how I would filter the signal from the noise without this.
I don't really bother about the vote count, but more the comments. A lot of stories I don't even read, I just go straight to the comments as I find them a lot more valuable (most stories you can get the basis just from the title).