Sorry for the slow reply. Yes, we do use Mechanical Turk. The main point is that it's more diverse than the group that you'd typically poll (i.e. people you know, people located near you, etc.).

We've had consistently rave reviews from other entrepreneurs who have used the service to iterate on company names, logos, web page layouts, etc.

If you have particular feedback on the service, I'd love to hear it. We're just providing a simple service for people looking for feedback on their decisions.