The blogosphere has a problem. It's something I would have denied the existence of back when I was a mere reader, that I could not possibly have noticed until I'd been in the business for awhile. It's not about the way its used so much, as I might have argued in my days as a reader, but something inherent. Nearly inherent, anyway.
The problem is this: the system naturally tends to form echo chambers. A good newspaper editor will bring in views from both sides, and hope people will buy when they see high quality and balance. A blogger however, wants links. There are two ways to go about this.
The basic way is to get the attention of other bloggers, one at a time. This can be done by either linking to the other blogger or e-mailing a post. In either case, it makes very little sense to try to attract attention from across the spectrum. The big guys won't care what a two-bit enemy is saying about them, and picking fights with little guys doesn't seem to make sense. Even if they take the bait and link, the blogger and his readers are unlikely to become long term fans. So the safest thing is to focus on like-minded bloggers.
A more sophisticated way that's sprung up since the 'sphere has evolved is carnivals. When these deal with controversy, however, they often embrace a single mindset. At most, you'll get people with incidental disagreement on other subjects. The exception is regional carnivals, though they don't do much good for talking about national politics.
Currently, the one way out of this problem is to try to attract attention from bloggers whose vies differ moderately from your own, but are close enough to make a real dialogue likely. This is why I pay attention to what Ambivablog says on science and religion, but finding such people is hard.
A few committed bloggers might be able to fight this however. I don't know the best way, but here's a few proposals:
A political version of God or Not, the carnival designed to unite theist and atheist bloggers. The idea is select a topic for each edition, and get people from both sides to submit posts. We could call it "Common Grounds" or perhaps "Spectrum Analysis" for analysis from across the political spectrum. (Also, that's what I'm doing in chemistry class right now). The model wouldn't work perfectly, however. With political categories being more amorphous, it would be hard to enforce balance. God or Not keeps the topics vague to allow many angles, this would be hard to do with politics. And religious debates are eternal, politics comes and goes, so it could be hard to declare a topic and then get people to write.
Other ideas: A site to pair up bloggers of radically different views who will agree to regularly resond to eachother's posts. A complicated cross-spectrum game of link-tag, not exactly sure how it would work.
I couldn't launch any of these on my own. Here's calling for help from other bloggers, in comming up with, refining, and implementing ideas.