The Windows Phone 8 SDK Preview has been leaked on the Internet today before being released in the coming weeks. What's included in the upcoming version?
Windows Phone 8 Developer Preview supports native C++ development and is able to support a significant subset of the Windows 8 SDK, allowing developers to share a significant amount of code between apps on Windows Phone and Window 8. The lack of native development support in Windows Phone 7.x has proven to be an issue with developers in the past, which has now been recognised by Microsoft.
The SDK Preview reduces the need to port and maintain components such as compute engines, graphic libraries, and API sets. Direct3D is also making its way to Windows Phone, which will enable developers to create and release games built using DirectX and share code base between PC titles (D2D, DWrite and WIC aren't supported). The supported vertex shader model version is 2.0, as is the pixel shader.