The key "trick" that he's using is to have unique, relevant, helpful content. That's the whole secret, imho, to good SEO ranking (obviously using the right tags, keywords, etc... helps).
He's just doing it backwards from what you and I would do, i.e. he's finding ad money, and building a site based on that, versus building a site, and then working on building traffic (ad based or not, you want traffic).
He's working smarter not harder. Finding a market and then delivering what they want, which is old news in business. He's just being tech savvy about doing it online. Most entrepreneurs build something they want. He's building a products that he has empirical proof someone else wants.
I wonder if that alone is worthy of a home based business?
He's done all his real work in qualifying markets to attack. If you did this then sold it to the zillions of people who want to make money with blogs, you might be on to something, and save yourself the google rath.
He's just doing it backwards from what you and I would do, i.e. he's finding ad money, and building a site based on that, versus building a site, and then working on building traffic (ad based or not, you want traffic).