Sharing your Outlook calendar with Exchange Server used to be a matter of all or nothing. You give access to your calendar or you don't. When others have access to your Outlook calendar they can see your calendar items, all of them! Exchange GroupCalendar however allows for simple but effective rules and formatting. You can now automatically publish to a central team calendar what others need to know and keep to yourself what they don't need to know.
Share only what needs sharing, automatically, in real time, based on predefined business rules. But there's more..

Suggested usage scenario's

Set up an Event Calendar (items entered here will distribute to all users' personal calendars).
Set up one group calendar where Staff can see only Staff items and Management can see Management plus Staff items.
Set up one company calendar per office and one global calendar with items belonging to a certain category from all individual office calendars.
Set up a Group Calendar to aid in task assignment.
Set up an Out of the Office schedule.