I found out that hard way that the 'config' hash in deploy hooks should now be referred to as '@configuration'.
config hash is now @configuration.
This is fixed in 2.0.0.rc1 and greater. Sorry for the confusion. The removal of config was not intentional (it wasn't really intended to be there in the first place but we also didn't mean to change behavior).
Sorry for the delay in response here. I'm going through and cleaning up all the pull requests in the engineyard repository.