CalPundit tries to figure out what it means to be moderate. Money quote:

First, there’s a difference between policy moderation and rhetorical moderation. John Kerry, for example, is probably about as liberal as Howard Dean if you look at his actual policy positions, but Dean uses more fiery rhetoric. Likewise, aside from a regrettable weakness for sarcasm, my writing tends to be pretty sober compared to someone like Atrios. But on actual political positions, we’re fairly close.

And that, in a nutshell, is why I take Kevin seriously but would rather get hit by a bus than visit Atrios again in my lifetime, and hence why Kevin actually has a decent shot at persuading me that he’s right on the issues.

James at OTB has more, including a money quote of his own:

Indeed, the mere fact that we spend a lot of time thinking, let alone writing, about politics and have developed somewhat coherent positions almost by definition puts us into the extremes.

I’d probably elide the “almost.” Having a coherent personal belief system puts you in the tails of the bell curve, at least relative to the public at large. I think moderation is more a function of whether you allow the belief system to dictate how you feel about people who don’t share your beliefs, and not so much what the content of your belief system is. Which, incidentally, gets back to what I was saying about political sophistication and perceived media bias.