[cpburns2009]

This is meant to provide an archive for the code. A major attraction of using GitHub is to allow easy pull requests and issues. If you're not going to be using those features, it's mostly useless when you already have your own infrastructure for hosting data. Lastly, if you're using a version control system other than Git, GitHub is not going to work well.

[akx]

You can set repos to be archived, i.e. read-only, on Github these days.

Besides, I find it a whole lot easier to just casually browse through code on Github rather than download 129 megs of eudora_w_source.zip, extract it somewhere and rifle through it...

[bdcravens]

The nice thing about Github is being to view the code easily, especially if you have a plugin like Octotree.