iCloud to Auto-Resolve Sync Conflicts
When it runs into conflicting data, Apple's upcoming iCloud service will automatically determine which is the correct one without bringing the user into it, according to Daring Fireball's John Gruber. Speaking on The Talk Show with Dan Benjamin, Gruber lays out what he believes to be iCloud's course of action in dealing with sync conflicts: (via MacStories)
In iCloud, I believe you will never be presented with [a sync conflict] dialog, no matter how much has changed in one of the instances while it was "offline". The server-side iCloud, when there seemingly is a conflict, will make a decision and it will decide which one is the best (in Apple's terms the "truth"). That is what Steve Jobs means when he says "The Truth is in the Cloud." iTunes will decide which one is right and that's it. iCloud will push that right one to any device that has this account that has a different version.
But, here's the trick – what happens if it's not the right one? On the server side, it will remember all of the other ones, almost like versioning. There will be some sort of interface like "go and look at your contacts." There will be some sort of way to say "show me previous versions and let me pick the one that is right". You pick it and push it back up into the cloud and tell it "that's the truth" and Apple will push it out.
Currently, MobileMe pops up a dialog box (shown above) forcing users to resolve conflicts, before a sync can continue.
Apple hasn't officially revealed many details about exactly how its new services are going to work, iTunes Match nor the other various bits of iCloud. Gruber claims this isn't just a theory, that he knows is sure this is how iCloud will work. We'll know more when iCloud launches this fall.