Mackrodd,
I like the look of the site, I do think that you should do something with the right sidebar there is just way too much white space on the side. Can be easily adjusted by adjusting the number of articles on the left.
Also your mobility resizing loses your menu. Are you aware of that? When you view the site on a phone in portrait or landscape the menu is not available. Mobility responsiveness is a big deal in SEO, is that intentional? If so make certain that it can be seen in the media queries, I could not find that area of the styles.
I see some things in the semantic makeup you may want to be aware of for SEO.
You using HTML5 document structure, that is good.
You are using a lot of Google Fonts which can make the site look really nice but you do not have fall back in the event that the Google Font link changes, which they do quite often, or the font is replaced. Fall back is critical to a good site structure, I would download those fonts to the site and directly link to a directory.
You have a lot of styles that are included on the page, both in-line and internal. That can really hurt your SEO. It is always a "Best Practice" to link all your styles to an external style sheet. There are many benefits to this especially as your site grows as the larger the content becomes the slower the page will load.
Just some suggestions to maximize your accessibility and SEO results.
Overall I like the layout and the site. The colors look good, easy to read and follow. I would add some type of slight contrast on the continuing reading pages. The content is well centered but without any contrast between the body and html elements it appears that there is a lot of white space on the sides of the pages.