Administrator privileges give a user rights to manage other user’s access to Google Apps or to perform actions that affect the setup of your organization’s Google Apps account.
You can make a user a super administrator with complete access to the Google Apps administrator control panel, or you can restrict the user’s access to specific tabs in the control panel. See Administrator privileges for details about which administrator actions are available from each control panel tab.
For More Info : http://www.google.com/support/a/bin/answer.py?answer=33325