Some of the people behind the openSNP website have been in touch with me for a while. As I put my own genotype into the public domain I'm obviously pretty well disposed toward this sort of thing. You should check them out if you haven't before, they just moved to a beefier server. Here's what they say they're about:
openSNP allows customers of direct-to-customer genetic tests to publish their test results, find others with similar genetic variations, learn more about their results, find the latest primary literature on their variations and help scientists to find new associations.
In this space I tend to focus on ancestry because you don't need any phenotypic information. You can just look at the relationships of the genotypes. But in the future traits are going to be where the real gold is. This sort of thing is a good first step.