It is a cliche in academia that the disputes are vicious because the stakes are small. I think this is a useful saying to keep in mind for bloggers as well.
One benefit of the internet is that it allows people who would not otherwise meet to discuss and debate topics of common interest. It is easy to forget, however, that relatively few people frequently traffic political blogs (still less, Catholic political blogs), or are even moderately politically informed. Furthermore, the people who do traffic blogs tend to already have strong opinions about politics/religion/culture, and so are the least likely to be persuaded on an issue of significance. The influence of any one blogger (or team of bloggers) is fairly limited.
I say all of this not, of course, to argue that blogging is pointless; just that it is not as important as the tenor of some of our conversations would suggest. It is easy in practice to confuse two very different things: 1) the importance of the issue being discussed; 2) the importance of a given conversation about that issue. What this suggests to me is that blogging is a recreational activity which should be of service in some small way to others and to the Church.
It is not a forum to say the type of uncharitable things one cannot say in face-to-face conversations, nor a place to vent, still less a place to carry on extended grudge matches with perceived ideological opponents. I have certainly been guilty of all of these behaviors at various points. However, as far as I can recall, the only times I have actually changed my mind about an issue in response to a blog post, the writer made a well-reasoned case that took counter-claims seriously, rather than focusing on polemics or personal attacks. I doubt my experience is atypical. This is a long way of saying three things: 1) Strong personal denunciations are generally unpersuasive, uncharitable, and unnecessary (alliteration!); 2) It is better to focus on the merits of arguments rather than the people making them; 3) The following cartoon proves that a picture is more valuable than three hundred and sixty-two words: