Same here! Since 3 days I don't have any push emails anymore. Sync between my Mac and the other iDevices is not working anymore. Strangely both iDevices are still syncing with each other. The iCloud sync icon in the menu bar is also showing a "No device for synchronization" message. What is that? @Tim: Please fix as there are many people with theses problems! Thx!
For a variety of reasons, including the AppleID/password fiasco and the upgrade from the pre-installed iOS 6 to iOS 6.1, I have lots of duplicate events. I went through and deleted the duplicates on my iPad and often they seemed to be deleted on my iPhone. Then I discovered they weren't deleted on my Mac!
I followed some advice about making sure the Mac was linked to iCloud, and now it seems to have gone to the worser! Duplicate events are back. Events that were monthly are now weekly! If I update an event on one device, it may or may not be updated on the others. If I delete a duplicate event on the iPad, both of the events may be deleted on all the devices! If I add an event to the Mac or the iPad, it appears on the other in a minute or so, but might not appear on the iPhone for five minuts or not at all
It's late! After all afternoon deleting duplicates and all evening trying to figure which way is up, I'm going to bed!