I must admit I haven't been following this thread thoroughly, but I am a member of a website with a rating system, so I can tell you how it is: You can give a comment and a rating from 1 to 10, or you can use a scorecard that helps you focus on the photographic qualities.
This is the scorecard:
And this is what it looks like when you've been scored:
As you can see it is anonymous, and it might be accurate if you get enough ratings for a picture, but: For me, this is not really informative. If my picture is rated low, I still don't know how to improve it. I don't really know how to learn from this sort of thing. I can learn something with the bottom comment, but nothing with the scorecard ratings.
Also, I think it doesn't fit here in Shuttertalk. I can only speak for me, but Shuttertalk has been like a family to me. When I get a picture, I'll share it. If some of you say it's great then I'll go to bed very happy, and if some of you don't like it I'm telling myself "They don't know nothing of true art".
My point is, however, that I enjoy the discussion with real persons - as real as they can get through an internet connection. I don't want my fellow photographers here to vote anonymously to give my picture a "rating". If I want my pictures rated, I can go somewhere else where I don't know anybody and don't mind if they like it or not - this would be just to have my picture rated.
Here it is different. I must say you all have grown on me, and I would take offense if someone I know would give me an anonymous rating. This would be like my neighbor slipping an anonymous note under the door to tell me to keep my cat away from their flower beds. Or so...
In case this post is too complicated, not very understandable or too sentimental, here is a short summary: I don't want rating. Even worse would be anonymous rating.
Edited: I might add that, due to the rating on this other website, I only post a picture if I think it is really good. I do not post any experiments or interesting pictures with slight technical deficits. In total I have three pictures on this site so far. I don't think this effect is desirable.