Apparently the realms currently offline - Cenarion Circle, Cenarius, Hyjal, Lightbringer, and Uther - are suffering from hardware problems and will require replacement parts. They're expecting the parts to arrive at 5:00 PM PDT, but are working on a temporary fix to bring these realms back up by 3:00 PM PDT (though this time-frame is just an estimate, and sometimes Blizzard is good about meeting these estimates and sometimes not). However, a temporary fix just suggests that there will need to be additional downtime later...

Update: Blizzard is giving a free day to the afflicted servers.

This article was originally published on Wow.
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