Previously, administrator privileges were assigned on a per-user basis. As a replacement, you can now create “roles” such as Help Desk, Services, and Groups, or create your own custom role.

If you assigned delegated administrator privileges to users before administrator roles were available, Google Apps created roles for those settings. These custom roles have the name role_useremail, where useremail is the email address of the user to whom the privileges were assigned.

For more information:
https://plus.google.com/117578386194324385666/posts/4hY2sPHti4R