The various groups within the CIM Users Group have the ability to share group calendar events with "roll-up" calendars. As items are added to their group calendar, if the item is designated to be shared with the roll-up calendars, those items will appear here, at the CIM User Group top site, and also possibly at the UCA site level.
This roll-up is constantly refreshed, collecting events across all calendars on CIM working group or task force subsites. Items are only shown if they occur today or in the future. Ability to access the links shown below will depend on your membership in the subsites where the event originated.