But the company shouldn’t stop at symbolic gestures. We love that the MS-DOS code is now available to the world at large (even if you can’t distribute your own changes to it, as with truly open source software). And we love that Microsoft has also released the code behind another seminal piece of software: Microsoft Word for Windows, originally released in 1990. But if the company is to regain its place at the head of the tech table, it needs to start open sourcing operating systems that are used today, not 30 years ago. Microsoft needs to open up the Windows Phone mobile OS — and maybe even desktop Windows.