I was thinking about that while responding but then you run into the same issue: how do you know the reviewer is any good? It's kind of like on the home improve

I was thinking about that while responding but then you run into the same issue: how do you know the reviewer is any good? It's kind of like on the home improvement shows when the new home buyers buy a house and realize it's a money pit and they all say, "but we paid for an inspection!" At some point there needs to be a trusted party and I personally don't trust any vendor until they've proven their worth to me- then I go back to them without hesitation. eLance/ODesk try and address this with reputation and customer feedback, which is probably as useful and valuable as some third party of unknown reputation.