Microsoft is preparing to include its Cortana digital assistant in the next major version of Windows, currently codenamed Threshold. Windows Threshold is expected to be named Windows 9 when it ships in spring 2015, and sources familiar with Microsoft’s plans tell The Verge that Cortana is a major area of investment for the release. Windows enthusiast site Neowin reported on Cortana showing up in early Windows Threshold builds, and we understand the current implementation is only a placeholder during the early stages of development. Cortana will exist across Windows Phone and Windows 9