A change has been made to the process around obtaining and API key to use the API.
Previous a user would have to log into the developers center and get an API, as well as logging into their account to get the second key.
Now, there is no need for the first step. A user should create or login to their account and go to Settings >API. If they have a valid email address as their username, they will see two fields with two API keys. These are the ones to use.
If they do not have a valid email address they will only see one API key and will need to get the other from the developers center (for now).