I think we all can agree that groups are a great way to manage folder permissions and make it easier to correctly assign proper permissions to a group of people quickly and consistently. However that speed and convenience is severely limited because there is now way of confirming what users are in a specific group when you are adding groups to folder permissions.
As an Administrator I at least have the option of cancel the folder permissions dialog box, going over the the Groups section in the Settings menu and viewing membership of groups but Power Users have no such luxury (as far as I know) and this is still a multi=step process that disrupts the workflow of managing permissions. Since users can make groups it seems to follow that they should be able to see the membership of existing groups. This way when they're selecting groups to add to folders and they are unsure if someone is in a group or not, they can check to ensure the permissions are set correctly so that data is not leaked.
One suggested solution would be when a group is selected in the manage folder permission dialog that the group becomes a clickable item much like an Outlook email recipient. If someone was to double-click the group it would reveal the group members so that staff and admins could quickly check to ensure the proper staff are being assigned permissions.