Thanks to everyone for contributing feedback on RPG Laboratory! The most requested features were a way to categorize posts and a navigation page for books.
In response, we've implemented a categorization feature for blog posts and book pages. They're not required, but if you would like your submissions to show up in related areas of the site, it's best to categorize them. If you think we need another category (or even a whole other topic), please let me know.
For the book navigation page, please point your browser to http://www.rpglaboratory.com/book or use the books link in the navigation menu.