A few comments on how rating works, and how to best use it (we're working on a HOWTO for the site, by the way, and we'll try to be clear on this stuff):
The rating system relies on people using it as much as possible, first and foremost. Ideally, bad rating would be drowned out by more people rating stuff, since everyone can rate, and it's not just a +/-1 kind of thing.
The idea is that you should rate according to where on the scale you think a comment should wind up. I very frequently over or underrate things because I know that my rating will average with others to produce a certain outcome. If I see a comment rated 1, for example, that I think should be a 3, I would probably rate it five. This will average with the one and land the comment at what I think it's final score ought to be. No, this isn't considered "cheating." :-)
Assuming that enough people are rating, the ratings will converge to a reasonable value. Sometimes a comment might only get one rating, and it happens to not be one that most people would agree with. Ok, bad things happen. I don't see this as being the norm so far. In my reading, it seems that if anything, people are having a tendancy to overrate-- most articles don't have many comments below 4, and few seem to have any below 3. Then again, I don't see many comments here that are less than average, so maybe that's accurate. :-)
I do hope that people don't rate according to their opinion. I mean, rating someone down because you disagree with them is just silly. Rate according to how much thought was put into a comment, and how well it expresses what it's trying to say. For example:
I would rate both of these '1'. Never mind that I agree with one and disagree with the other, neither one says anything particularly worthwhile.
And the final point is, don't put too much stock in what ratings your comments get. K5 is not the ultimate arbiter of you as a person. Ratings here, in the grand scheme of things, have no relevance outside this small closed software system. If some jerk mis-rates you, you can at least have the satisfaction of knowing that you don't do the same to others, and that ultimately, it means nothing.
I agree with those who said give it some more time, and see how it holds up. And meanwhile, the very best way to solve this is to rate more! Even if you don't normally rate comments, keep an eye out for ones which are drastically misrated, and rate those. It only works if we all do it, pretty much.
Not the real rusty