The iCal data on my iPhone and on the MacBook won't sync, not over iCould nor via iTunes. It doesn't work either way (phone-mac or mac-phone). Syncing worked via iTunes up until 3-4 weeks ago, then stopped working alltogether. Ideally, I'd like it to work over the Cloud so it updates real time.
I downloaded and upgraded to Mountain Lion (10.8.2) yesterday on my MacBook Air, hoping it might solve the issue. I deleted the iCal cache files in Finder/username/Library/Calendar, made a back-up of all the iCal data, removed all date from iCal and reinstalled it, tried to switch off my iCould account and turn it back on, etc - nothing worked. The one thing read in previous threads indicated to refresh 'reset sync data' in iSync in the Applications folder, but my Applications folder is showing as empty in Finder (even though I activated the hidden files and can see them). My phone is a 4S
All other data (contacts, music, photos, etc) is syncing just fine.