Adam Felder, who does analytics atThe Atlantic, has an interesting post showing how nasty comments sections might turn off readers. He ran an unscientific experiment in which he asked respondents from Amazon's Mechanical Turk work-crowd-sourcing service to read two versions of an article and then answer some questions about it. One version just had the article; the other had the article, followed by a representative sampling of the (often terrible) comments that had been left on it.
The negativity of the comments, it turns out, spilled out onto readers' perception of the article itself — those who read the version with comments rated the article as lower quality. This makes sense — if things like an article's layout and the prettiness of the webpage it's hosted on affect our view of it, why shouldn't the comments we see immediately below? At first glance, then, this is an argument for banning comments sections, which a fair number of publications have done.
But I still think it's not that hard to put the trolls in their place. The goal shouldn't be to get rid of horribly, nasty commenters altogether, since that's impossible, but rather to render them almost invisible, to give the average, non-horribly-nasty reader a sense that they are in a reasonably civil place.
I did a roundup of different publications' approaches to this problem a couple years ago, and I was struck by the sheer number of options. As technology improves, it will only get easier to lock the trolls in a cage with each other. On articles with lots of comments, for example — and these tend to be the trolliest — as long as there's a way for editors or moderators to lift decent, thoughtful comments to the top of the pile with a single click, that could make a huge difference. Readers will get to the bottom of the article and say, "There's some decent conversation going on here." Reddit's a pretty good example of how this works. Yes, there are a lot of immature jerks on there, but because individual comments can be voted up or down (a system lots of publications are adopting), it also isn't hard to find good conversation (and/or epic pun thread).
So for those publications not willing to get rid of comments sections, this should be the approach: Let the trolls do their thing, but let them do it to each other in some dark cave somewhere, leaving the rest of us alone. Now please leave your thoughtful, well-articulated comments below.