Octopress is a framework designed for Jekyll, the static blogging engine powering Github Pages. Thanks to Octopress, code blogging is easy and beautiful. I like the way how Octopress is documented: simple and useful. Make sure to spend 30 minutes checking them out before using it: Octopress Documentation.
As Brandon Mathis stressed, Octopress is a blogging framework for hackers. But don’t think of Octopress as something extraordinary and complex. At least, you should be comfortable running shell commands and familiar with the basics of Git. How to know if it’s the right tool for you? Just feel the joy then it’s perfect for you!