In fact, I'd almost prefer a comment service start serving up porn on my blog. At least it should, presumably, be fairly clear that it's spam, and not something I've actually endorsed. This "recommendations" feature is essentially Disqus abusing the fact that they can generate content on my site to do one better than the comment spammers they protect us from, and make it look like I'm endorsing their random links. Spammers' wet dream, really (the fact that they're links to well-known publications and not virus-laden sites notwithstanding).