User interfaces are a fundamentally important part of most applications. Making those interfaces as effective has possible can have measurable benefits to the people and organizations that rely on them.
With Windows Presentation Fundation (WPF) developers now have an added option to (.NET) Windows Form to use when they need to implement a user interface.
David Chappell just released an interesting white paper available on www.windowsclient.net with a very clear view on WPF 3.5 and its positioning versus existing technologies like Windows Form.
I found very interesting the following quotes:
"[...]In fact, even with the arrival of WPF, some applications will continue to use other interface technologies. Windows Forms, for example, is clearly the right choice for anything that must run on systems where WPF isn’t available, such as older versions of Windows. New applications might also choose Windows Forms over WPF for other reasons. It’s important to understand that while Windows Forms has proven to be an effective interface technology for line-of-business (LOB) applications, WPF (today, at least) targets a slightly different problem[...]"
"[...] Another option is to combine these technologies, using aspects of WPF and Windows Forms in a single application. This is certainly possible, since each technology is capable of hosting user interface elements, known as controls, defined by the other. For example, Windows Forms provides a useful DataGridView control that has no analog in WPF, while WPF offers many things that Windows Forms does not, such as 3D graphics and animations. [...]"
I read between lines that windows form is not dead and can continue to be used in specific scenarios.