The question, though, is how blogging will change as it becomes democratized and the blog-reader's profile grows increasingly representative of the population at large. My guess is that blogs will retain many of the characteristics they posess today; to put it another way, bloggers I think are more "in touch" than their incomes suggest.
Just thinking of families I know, the main predictor of internet access is whether or not they have a kid who grew of age in the internet era. Income is less important. I was surprised to see that the dailykos readership spans a wide range of ages and centers much higher (30s+) than you would expect; that doesn't square with my personal experience.