With the blog re-design I had two primary goals... First, to howcase the author's photographs in the best possible light. This is done by allowing images to spread slightly wider than written content. The darker framing of captions helps the image colors to pop off the page.
My second goal was to improve the visual clarity by which comment responses were displayed. Previous iterations didn't provide very many visual cues to which comments were responses by the post's author, so both highlighting them and nesting them helped drastically.
The site's registered members (called Explorers) have the ability to upload an image that is associated with their timeline and profiles. If a blog comment is made I opted to use the image they've uploaded (rather than a standard Gravatar.com image) to maintain visual continuity between the blog areas and the associated Explorer profiles.