A screen displays the logo of Microsoft's Windows 8 operating system at a press conference for its launch on October 25 in New York City. The company kicked off sales of the system and its Surface ... more 

A screen displays the logo of Microsoft's Windows 8 operating system at a press conference for its launch on October 25 in New York City. The company kicked off sales of the system and its Surface tablet Friday amid mixed reviews as the tech giant ramped up efforts to compete in a market shifting rapidly from PCs to mobile devices less