On November 6, 2012, Libertarian Party member John Inks was re-elected to the Mountain View, California, city council. And on the evening of January 8, the city council chose him as Mayor. See this story, which explains the traditional method by which Mountain View city councilmembers choose one of their own to be Mayor.
Mountain View has a population of 74,066, and is the headquarters city for Google, Intuit, Mozilla Foundation, and Symantec. Thanks to Independent Political Report for the news.