This is an interesting post, giving a couple of examples for a case study on how to choose a niche for your blog. I wonder if the reason the second blog mentioned is more successful is because it enjoys the benefit of TrustRank on the typepad.com (sub)domain. Another thought I had about this, which also probably never occurs to many bloggers who read Darren’s blog is that in a way it’s rather absurd to select the topic for your blog based upon what you think will be successful in Adsense. To me, that’s somewhat like putting the cart before the horse, or even trying to get your cart to go without the horse. Aren’t blogs supposed to be for people who have something to say? Well, maybe not, but at least I think it’s a bad trend to see bloggers choosing topics based on what’s going to make them more money. I do see this “Made for Adsense” trend leading us in the same direction as email. Are MFA sites the web equivilant to spam in our email?