I've made it a principle to leave accurate, detailed, and positive reviews on Amazon for products I really like. I think I've mostly given up, I don't think they can move the smallest needle if the environ is so deeply poisoned. The only honest and constructive feedback commerce site I still use and participate in is King Arthur Flour, probably because the stake is so small. I mean, how many reviews for a $18 bread pan can one flog? It reminds me of Goodreads, before Amazon. The larger question though, is whether or not high-trust systems can ever scale, or even be extended to cover an adjacent domain.