I can’t comment on the methodology — not all blog posts are equal — but this claim is interesting:

If blogs are critical in the current battle for public opinon, then there may be real cause for concern: according to our sample of almost 2500 political sites and blogs, conservatives are winning hands down, with almost twice as many posts as the progressive side (4642 posts vs. 2785 in the past 15 days).

Meanwhile, have you seen NRO’s Critical Condition?