This site is running Habari, a state-of-the-art publishing platform, still officially beta, but nevertheless quite usable. Habari is a community-driven project created and supported by people from all over the world.
So far it's an experiment, I may try out other Open Source blogging software as well. For now, I like what I see (except I'd like to see more themes, but I'll probably end up making my own anyway). I'm also getting a lot of help from Habari users & developers in the #habari IRC channel on FreeNode - there's a real sense of community and cooperation there.
Installation was a bit of an adventure (in keeping with the main theme of this blog); not because it's difficult but because I made it difficult for myself by trying to put (almost) everything away from the document root and symlinking to it, so the code base could be shared with possible other installs - except the user directory which would gather its own plugins, themes, etc. Turns out my reasoning was correct - it almost worked - except Habari doesn't support symlinking to plugins yet. Once I had real copies of the plugins instead of symlinks, everything fell into place. Just like me to not start with the simplest option.
Please visit http://habariproject.org/ to find out more about Habari!