Of course, I never claimed that such a system would be without pitfalls. But isn't most people mature enough to not go into 'rating wars', and wouldn't it be possible to minimize the amount of such wars ? Perhaps you would need a certain amount of '+1'-posts before you were allowed to make any feedback actions ? I posted a thread about 'good post'-rating aka +1 aka karma rating before. I don't have the link.
Point being that when introducing a feature, it's always good to discuss the negatives and the positives.
Allowing rating only after some fixed condition is by no means enough to produce a stable and reasonable result. In fact, it worked just like that on this very forum in the past -- and was a catastrophe.
Rating anonymously is probably not a good idea. It makes voting someone down "just because" way too tempting. Also it reduces the amount of useful information; it's sometimes interesting not only to see how someone has been rated, but also how he rates others. To setup a rating system properly, one has to dive into game theory and show why both the likely and the optimal behaviors of players are also the desired behavior. There might be a way to do it right. Yet I prefer no system to a broken system. Better leave it up to competition from elsewhere.
One way I could imagine as useful: a WoT-like system that lets users select whose opinions they value, and over how many "hops". So everyone is still responsible whom to trust, but it becomes more efficient: if I add Vladimir, and he rates someone "danger, stupid Ponzi", I'm safe no matter how many shills shill for the target. However, if I'm insufficiently informed and add all the shills instead, I'd fall to a "+9001 super duper trustworthy" scammer.
Long story short, I believe in consensus, but I prefer to pick the people who get to add to it.
Then again, this is how the #bitcoin-otc WoT can be used if you know the right commands or browse it manually. So there we have this solution already, albeit it could use a propped-up UI.
FYI, this is a special case of a general,
huge class of problems. Possibly the biggest problem of cooperative humanity. How do we enable someone with limited knowledge of a system to classify the people in it? Put another way:
is there a method that enables a fairly uninformed person to reliably distinguish a populist politician from an economic expert?