Great news! You can now customize what admin sections staff members have access to. Simply navigate to your Account area, and click on a user's name. There you will be presented with the option to give that user full access, or to customize what permissions he has. Please note that only account owners can make those changes.
A user with limited access is able to see what permissions he has, and what permissions other users have.
Furthermore, links that are restricted are greyed out of their navigation bar. Clicking on one of these links brings the user to a page similar to the following: