The North American Aerospace Defense Command, also known as NORAD, is changing sides in the search wars -- at least when it comes to its annual mission of tracking the Christmas Eve flight of Santa Claus around the world. The Colorado Springs-based joint U.S.-Canadian military command this year has switched to using mapping technology offered by Microsoft Corp.'s (Nasdaq: MSFT) Bing search engine from search leader Google Inc. (Nasdaq: GOOG). NORAD has tracked Santa Claus through the sky on Christmas…