How to create interface for C++ application with XAML? (I SEARCH FOR SOME APP LIKE EXPRESSION BLEND (OR even beter a plug in for it))
Visual Studio Pro 2008 does support C++ .Net and XAML interface designer so it should do what you are looking for.
PS : Visual Studio 2010 is going to be released soon. I never tried XAML with this one but it should have a better support.