Windows Forms will be around for a long time, since it is an integral part of the .NET Framework. That being said, there are no new innovations planned for the WinForms technology as the new, preferred UI platform is WPF. The drawback to WPF right now is that the tools aren't available yet to make development as easy as it is for WinForms. The other concern for WPF is that it isn't yet applicable to every application. There are some things that are just better done in WinForms right now. The best approach is to separate the business logic and the UI as much as possible. This will allow you to gradually migrate to WPF from WinForms when it makes sense. Also, you can combine WinForms and WPF in the same application, with a few technical limitations on the interop.
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