Good link. At the end of the day, they're doing association studies... So they're taking a phenotype (even survey answers are a "phenotype" in a manner of speaking) and correlating it with a genotype (whether SNPs, exome data, or genome data). I'm a believer in this approach to science and am in no way poo-pooing their effort; I merely wanted to comment that, from the article's description of their approach, they're doing nothing iconoclastic.
http://en.wikipedia.org/wiki/Genome-wide_association_study