I don't mean to be all, "ugh," but syntax should be at the top. Looking at that shot, as opposed to the one in the blog post, it will be common for syntax sections to fall off the bottom of the screen, "below the fold." This will make it less useful than sites that don't require the user to scroll to get the most basic information, such as method signatures, and MDN will continue to be a second choice.
OK, that all got a little sharp, but I do wonder what "design language" (per the blog post) is steering their information design.
I agree, but I don't think going through and reworking any actual content of the articles (these are all essentially wiki pages) is in scope for this stage of the redesign. 'atopal mentioned elsewhere in this thread [0] that they're doing this incrementally, and the next phase will be dedicated to article page layout.
You might want to mention this on the accompanying Discourse feedback thread [1] so it's noted for the next phase.
