I granted permissions to the app via GitHub, then I get:
Internal Server Error
Now, however, if I click on the "Sign Up" button on your homepage (http://team-name-goes-here.2013.nodeknockout.com/), it sends me to:
http://team-name-goes-here.2013.nodeknockout.com/auth/github...
and the same page simply saying:
Internal Server Error
So it seems that Github obviously granted something to your app, but now it's broken for me? It would be nice to try this out.
On another note - some screenshots on your homepage would also be nice.