Apple’s system status page is showing that iMessage and four iCloud services – Photostream, Documents in the Cloud, Backup and iPhoto Journals – have been down for some users for more than six hours … 

Apple says that fewer than 1 percent of users are affected.

Users may have been unable to create a new Apple ID.

Most Apple outages are relatively brief and affect only a small minority of users, but its Developer Center was offline for a week after a security researcher pointed out a vulnerability that could expose user data.  Apple introduced a similar status page for its developer portal during the outage.

Update: After 11 hours and a short period of time where the iTunes Store wasn’t available to some, all services are now back online.