A blown transformer in the Fisher Plaza building (home to local ABC affiliate television station KOMO-TV and KOMO Radio) in downtown Seattle has affected a data center there, and Bing Travel among numerous other sites have been affected.  An explanation is up at www.bing.com/travel:

Sorry, travel isn't available just now

A fire occurred at Fisher Plaza in downtown Seattle just after midnight on Friday morning. The blown transformer knocked out power to the entire building, which is home to the Bing Travel servers. This is isolated to Bing Travel only, and there is no impact to any other aspect of Bing. We're hard at work to restore service following this unexpected event.

Our current estimate for re-establishing Bing Travel functionality is 5pm PST, July 3rd. In the meantime, you may use Microsoft travel partner Orbitz for your travel needs.

The fire reportedly lasted only about 10 minutes.  Todd Bishop from TechFlash is on the scene, and has updated reports.

Any guesses as to why Bing Travel is hosted at Fisher Plaza and not at one of Microsoft’s data centers?