iCloud Mail Unavailable for Some Users

Apple's iCloud Mail servers seem to be experiencing some downtime, with multiple reports on Twitter suggesting the service is unavailable for a number of users.iCloud Mail issues appear to have started just before 2:00 p.m. Pacific Time, which is around when we here at MacRumors first noticed problems with our own accounts.
Affected users are seeing pop up alerts when attempting to access their iCloud Mail messages. Some alerts are blank, while others let users know there was a problem loading M