The most interesting thing about this article to me is where the author got the data -- http://www.aggdata.com .

I ran across aggdata some time ago while looking for a list that they happened to provide for free. They provide niche data that they scraped from the internet. Their data is cheap enough that it's not worth trying to scrape the data yourself. I think the business model can be duplicated easily and there is plenty of room on the long tail.