Note: I\'m not a newb, and I\'ve done this a gazillion times, but for some reason today it decided not to work.
I keep getting the Permission denied (publickey).>
I had a similar problem, github did not use my SSH key. I always had to enter my username and password.
I've been looking at .git/config, under [remote "origin"] there was:
url = http://github.com/path/to/repository
or
url = https://github.com/path/to/repository
I changed the line into
url = ssh://git@github.com/path/to/repository
and then it worked.