I think that maybe I've put my arguments forward in a bad way. I'll try from a different angle.
In business strategy there's a concept called complementary products. A complementary product is one that is one that makes your product more valuable the cheaper it is. Cars and gasoline is an example of this. Servers and software is another. The cheaper gasoline is, the more valuable a car is. The good strategy is to commoditize your complements, thus driving down price. This will put more value into your product. For instance, if you run Google you make software. Your interest is to comoditize servers, thus driving the price down. This makes your business more valuable because your complement has been commoditized. Indeed, this is exactly what Google is doing when they use standard boxes in large arrays instead of buying Sun servers.
My argument in the blogpost is similar. If Google can remove as many obstacles as possible, and commoditize their complementary products they will win. This is exactly what they are doing with this move. They are forcing their competitors into making a product that will make Google money. Google doesn't care (financially at least) about browsers and operating systems. They make their money on online apps and marketing. Their strategy is to make it as easy as possible to get online and use their services. The argument is underpinned by the fact that both are open sourced. They won't make Google any money directly, but they'll help tremendously in commoditizing OS'es and browsers.
Joel Spolsky has a post about omplementary products that explains the concept much better than I can ever hope to do: http://www.joelonsoftware.com/articles/StrategyLetterV.html