Every Django Developer has written its own Django-based blog. But most of them have a lot of features, that you’ll never use and never wanted to, or they are just too simple for your needs, so you’ll be quicker writing your own.
Following the principles of FeinCMS, ElephantBlog tries to offer simple and basic blog functionality, but remains to be extensible so that you just pick what you need. And if you don’t find an extension, you can quickly write your own and integrate it to ElephantBlog.