Dan Edelen over at Cerulean Sanctum has some convicting words to say about the "heresy watchbloggers." Very well written - check it here.
I had some frustrating experiences with one blog of note. I commented on several posts there, but they were never accepted in the meta. Probably not accepted because my comments were not in agreement with the person's posts, but I was certainly not disrespectful towards them. Going through the meta of most posts, I saw very little disagreement with what was being said. It's one thing to monitor comments for language-control purposes (e.g., blocking out curse words or slanderous statements), but it's quite another to only disallow comments just because the person disagrees with you.