The next version of Microsoft’s Windows Phone platform will finally bear fruit in September when a phone featuring the Mango update will hit Japanese shelves. The software giant has company has now officially signed off on the RTM version off the OS and in a blog post, Terry Myerson, corporate vice president of phone engineering said that this, “marks the point in the development process where we hand code to our handset and mobile that operator partners to optimize Mango for their specific phone and network configurations.”