There is some dirt out there (written by people banned from my blog) that I do not post things with which I disagree. This is a lie. Just look at the recent post by "Atheist Missionary," for example. Some times I post things that criticize what I have written and never even respond to them. This is usually because I do not have the time to do so.
The issue of whether someone gets rejected or banned is the tone and tenor of the pieces. If someone merely hurls insults and invective, they don't get posted. If they do it long enough, I enforce an a priori
ban, which means that posts from X go to spam automatically or I reject them unread. There are probably a total of five people on this list. (However, I just offered a banned person the chance to reinstate him or herself if the posts are not in the objectionable category. I also happen to know this person outside of the blog "world," although not well.)
And who thought the Internet would improve social discourse?