On a side note, I hate that the access credentials are labeled “Developer” credentials, it leads to basic misunderstandings. If the seller runs MWS software locally, they will need access to their own “developer” credentials regardless of who wrote it.
Evan’s statement (and the registration documentation) about not needing developer credentials is only true for cloud applications, or other instances where a developer is controlling a server running the request on behalf of another seller. I am too old school to think software only runs in the cloud.
The documentation Evan linked to appears to be updated, it has the links to register for MWS, the user permissions page, the manage your (cloud) apps page, and the new contact MWS link for resetting your own credentials.
It would be nice to know when stuff like that changes, and if there really is a delay before approval for new developer credentials now.