WARP10 is a new component that will be part of DirectX graphics technology in Windows 7. WARP10 is a high speed, fully conformant software rasterizer. It is shipping in beta form in the November 2008 DirectX SDK. WARP stands for Windows Advanced Rasterization Platform. This paper describes the following aspects of WARP10.

One of the major advances in Direct3D 10 was the removal of caps. This removal allows developers to take advantage of all the features of a wide range of video cards knowing that their application will behave and look the same everywhere. The performance of these applications can be scaled by simply disabling expensive graphics features on low end cards or rendering to smaller targets. WARP10 contributes to this ‘No Caps’ goal by allowing developers to have access to all Direct3D 10 graphics features, even on machines without Direct3D 10 graphics hardware.

By providing WARP, development is simplified by removing the need to spend time building a custom software rasterizer and tuning your application for it instead of hardware. By providing a single, conformant general purpose software rasterizer, there is no longer a need to write image rendering algorithms in multiple ways simply to run on hardware or software with different features and capabilities.

You can read the entire article at MSDN.