Note that this change will only effect you if you are:
- Using a Mac
(does not apply to you if you use a Windows PC)
- Using MobileMe Calendaring
(does not apply to you if you use iCal without using MobileMe, or use a different calendaring application, such as Outlook 2011 for Mac)
- Wanting to do a 2-way sync of their MobileMe Calendars to non-Apple mobile devices
(you will still be able to sync calendar events 1-way, desktop to device, even after the Apple forced upgrade)
For full details of the changes, and a number of options for those effected, please see our knowledge base article on this topic.