So, for example, a domain shared resource calendar setup for employees to post notice of leave/absence. When an appointment/event is added to that Calendar, it would be nice to have the office manager receive notice that a change was made to that calendar via domain events configuration set the email them when a change is made to the calendar. Same with personal calendars - if a user shares a personal calendar to say - a secretarial assistant - the owner of the calendar may like to get a notice of the change to the calendar via a My Settings...Events configuration.