"iCloud stores your content in the cloud and wirelessly pushes it to all your device. It automatically uploads it, stores it, and pushes it to all your devices." And by "automatically," he means it: in addition to "every day content," such as purchased music, books, photos and videos, device settings, and app data that will be automatically backed up over WiFi, Documents in the Cloud will effortlessly sync Pages, Numbers, and Keynote data between all of your iOS devices. There will be no advertising (contrary to previous rumors), and calendar, mail, and contact sync is free.