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Turns out the problem was indeed a data center fire (which is a truly frightening prospect). As best I can tell, a transformer shorted out and started a small fire. Sprinklers kicked in and put out the fire but also shorted out generators and caused much more serious problems. Ultimately, all power to the building had to be shut down, which caused issues on a huge scale. Loss estimates run into the tens of millions of dollars when you figure in lost sales online, etc.