I've seen the people posting issues, and you have to scroll down to read the coments, and what you see? A bunch of "+1" as comments. So the "comments", instead of being a place for debate and discussion, has become a place for... VOTES.
So what about a button (may be like the stackoverflow, wich is unintrusive) to upvote or downvote an issue (or a comment), and leave the comments part only for dicussion?
From time to time there are good ideas in the comments too, and we can avoid the: me too, +1, it's a good idea, etc...