[kappuchino]

Its better paid than Amazon Mechanical Turk afaik (not saying it should not be paid better). The tuning is done literally by thousands world wide and since every rating task is done by multiple quality raters (afaik side by side is done by at least 5), it seems to be a cost vs. scale factor.

[demadog]

Amazon Turk is more of a platform for small business to hire other workers for micro-tasks. Raterlabs is used only by Google to improve their core product.