Github is interesting is that the code is shown front-and-center whenever you visit a project page. Sure there is the Readme.md and wiki stuff you can do, but it makes browsing code and project discovery very easy. Github also made project creation and management super easy and lightweight. The number of questions you need to answer to setup a repo is so minimal. It gets out of your way when setting up a project.
I still feel like Google Code has some things going for it. The biggest being it's defect tracker compared to Github.