I am very happy to see codeguru hosting a dedicated WPF forum. I hope it takes off ( It should! all the experts here seriously need to start thinking about WPF, if they want to preserve their cutting edge on software development ) It will make you think your starting all over again. Well, you are starting over again. There is a nice advantage in understanding .net, but as you progress just a little bit into WPF, you'll quickly realize just how much you dont know. I say this as a challenge, afterall thats why some (or most) of us develop software. For the challenge, and the personal satisfaction of knowing that "you did" and "you can".
I've seen some amazing projects in WPF, that a straight c#,c++, or vb developer could only dream of making (in any reasonable amount of time).
Remember, vs2010 visual interface is supposedly entirely written in WPF. Say yes to WPF. Microsoft seems to think so. GDI has been fired!
Consider this book to get you going:
Pro WPF in C# 2008
Windows Presentation Foundation with .NET 3.5
Second Edition
Matthew MacDonald