I am currently working with my third client to deploy develop a WPF application. The first was a LOB application for one of the 3 major shipping providers in the US, the other two for smaller companies.
I find Visual Studio to be perfectly stable, but I also never use the designer in Visual Studio. Expression Blend is perfectly stable, if not missing many features expected by designers.
WPF uptake is surely slower than language features introduced into Visual Studio & .Net, but it is far superior to WinForms in many ways and will be the future.
Go learn the WPF mindset and you'll never go back.
