|Several of Apple's online services continue to be non-functional for some users after they went down at 12:30AM Eastern, according to Apple's system status tracker. Perhaps the most critical ones are iMessage and iCloud backup, but several other iCloud functions are also out. These include Photo Stream, Documents in the Cloud, and iPhoto Journals.
Apple states that "less than 1 percent" of users are affected, but services have been impacted for over eight hours, and there's no estimated time for when they'll be completely restored. The company has been hit by a number of online service disruptions since late 2011. Many have been related to iCloud, but not all; recently, for instance, Apple deliberately took down the Developer Center to make security improvements after a hack exposed its weaknesses.