New media people spend a lot of time thinking about the comment issue. A lively comment thread at the end of an article drives up readership and create a sense of intensity. In a model that's working pretty well, people get excited about the comments, which become almost a second part of the story.
But there's another, slighty darker, part of all this. A law passed back in 1996 holds publishers harmless for just about anything that appears on one of those threads. In fact, those comments are basically considered not to have been published. They are not the act of a publisher in the same sense that a publisher publishes a letter to the editor. Which means that if you want your comment sections to turn into an insane sewer, you can let that happen and probably never have to pay the piper.
So the trend in mainstream publishing is to let those comments flow up onto the site without any pre-screening and then maybe fix them -- maybe -- later. The downside is that this kind of environment will scare some readers away. One solution is to interact with the commenters. There's a huge amount of related content about comments up at Poynter because they've been such a problem.
If I were starting a new site -- maybe not one with the current personality of CNP -- I would consider premoderating all comments but then having a segregated section -- maybe call it The Inferno -- where anybody could say anything. Enter at your peril.