Heroku and git seem really cool at first until in I ran into a problem when working on windows 7. It looked like I was doing all the commands right to push my files up to heroku.
git push heroku master
but, it kept failing on the key.
Turns out when heroku first creates a project it copies up your public key. For me it was here
But, when git runs it was pulling from a file here
The only way to fix this was to push the id_rsa.pub key directly with this command
heroku keys:add C:\Users\paulin\AppData\Local\VirtualStore\Program Files\Git\.shh\id_rsa.pub