I'm torn. There are definitely differences between the way Less Wrong operates and the situation the article describes, but that's always going to be the case. It would be nice to see more studies, of course, examining how the details of the system matter, but no such seem to be available. Absent that it kind of seems like special pleading to say "we do things slightly differently, so obviously it won't apply to us." On the other hand, only one study is rather weak evidence, and the differences do exist, even if we don't have any actual evidence that they matter. I really don't know if it makes sense to consider changing our system in light of this.
This article discusses how upvotes and downvotes influence the quality of posts on online communities. The article claims that downvotes lead to more posts of lower quality from the downvoted commenter.
From the abstract:
Social media systems rely on user feedback and rating mechanisms for personalization, ranking, and content filtering. [...] This paper investigates how ratings on a piece of content affect its author’s future behavior. [...] [W]e find that negative feedback leads to significant behavioral changes that are detrimental to the community. Not only do authors of negatively-evaluated content contribute more, but also their future posts are of lower quality, and are perceived by the community as such. In contrast, positive feedback does not carry similar effects, and neither encourages rewarded authors to write more, nor improves the quality of their posts.
The authors of the article are Justin Cheng, Cristian Danescu-Niculescu-Mizil, and Jure Leskovec.
Edited to add: NancyLebovitz already posted about this study in the Open Thread from September 8-14, 2014.