Jekyll and other static site generators are, currently, harmful to the free, open source software movement
My blog is powered by WordPress. WordPress remains at its core a monstrous amalgamation of PHP spaghetti code. Thus, despite the fact that WordPress is free (beer+speech), easy to use, well supported, well documented, and all that jazz... it still pains my hacker sensibilities to use it. For similar reasons, a lot of hacker types are moving away from WordPress and similar blog software to static site generators like jekyll.
Basically, the idea is that you define the components of your site (pages, blog posts, etc) in a text-based markup language, and then the static site generator will process the text files and produce static HTML files for your website. This approach has numerous advantages, mainly due to the fact that no code runs on your web-accessible server. This makes it both fast and secure. But static pages have one major drawback: if everything is just static HTML pages, there's no easy way to allow for dynamic features like comments (and, to a lesser extent, search). Using something like WordPress, you get dynamic features automatically.
But there is one problem: Disqus isn't open source. So we have all these hackers rushing to switch their blogs over to static site generators with Disqus comments, which is effectively an exodus from completely free systems like WordPress to proprietary systems like Disqus. I find this to be problematic for all the same reasons that RMS and others have outlined about proprietary software (and also software as a service) over the years.
But the allure of these static site generators is such that they feel like they are the pinnacle of open source hackery goodness. The generators themselves are generally open source, and they work similarly to all the open source command line tools we know and love. But, until there is a better solution for comments than Disqus, static site generators encourage dependence on proprietary software.
So I guess what I'm saying is that we need an open source (preferably AGPL) Disqus. Or, if such a service already exists and I've just not heard of it (certainly I'm not the first one to make this point), then we need to do a heck of a lot better promoting it. Otherwise, all the user-generated content in the form of blog comments will be perpetually locked in Disqus's proprietary vault.
Edit 2012-02-02: In the comments, Haschek provided a link to a project called Juvia which is "an open source commenting system ... similar to Disqus and IntenseDebate". If you have the same concerns as me, take a look at Juvia if you're in need of a standalone commenting system.
Edit 2017-01-22: Uh... I think I'm moving this blog to a static site generator, for all the typical reasons. What about comments? I think... no comments. I guess that's kind of sad, but comments seem like more of a marginal benefit now, at least for my rarely-updated blog.