Bob Wertz wrote a How To called Easy Category Pages in Navigation on Micro.Blog:
It shouldn’t matter what theme you are using, but for my site, I use the Pure plug in, which is a good foundation to build from. By default, the template presents a home page that includes all of your posts. Instead, I wanted to have different links in my navigation for my longer “blog” posts and my shorter “tweet-like” status posts.
Read the details at his site.