Why WPF?

According to Tim Sneath, the graphical subsystem that forms the heart of the Windows user experience (the USER32 and GDI libraries) is actually now approaching its twentieth birthday, having debuted in the first version of Windows. Of course, USER32 and GDI have undergone substantial evolution and development over that time, with the introduction of many new services and capabilities in all areas. New presentation technologies such as Direct3D have also come along that take full advantage of the explosion of graphics capability in recent video cards. But most mainstream applications today don't deliver the experience made possible by these graphics cards.

Windows Presentation Foundation (formerly known as "Avalon") is the new strategic graphics subsystem in Windows that provides a unified approach to user interface, 2D and 3D graphics, documents and media. Built on the .NET Framework foundation and utilizing Direct3D for vector-based rendering, it provides a powerful solution for building immersive applications of all kinds. Furthermore, Windows Presentation Foundation enables designers to be an integral part of the development process by providing declarative programming models for "toolability" and flexibility.