CalDAV as an addon to a calendar service. Many people can use the CalDAV service with Windows Calendar or Apple iCal.

As a user of GoogleCalendar, it would be very useful to be able to add the calendar from it's learning via  iCal, instead of being forced to manually enter the entries from it's learning to GoogleCalendar. Naturally, iCal can be used by many other calendar softwares than GoogleCalendar.

This will lead to further compatibility for iPhones and Windows Mobiles since those can be synchronized the it's learning calendar by making an array e.g. through GoogleCalendar.

This feature is needed!