WPF applications are, at its core, managed applications? Right? So, I have to choose between using managed C++ or managed C#. I experimented with managed C++ years ago. It seemed to be not quite be ready for primetime. I'm guessing Microsoft has put more effort into managed C# than managed C++. So, it seems like using managed C# is the best alternative between the two. Is this the case? What experiences have you had with WPF in either language? Thanks in advance.
Managed C++ has been replaced by C++/CLI, and "managed C#" is just C#.
I would strongly recommend you to use C# for a new project, and use C++/CLI only when needed. C# has a better support, has a larger user base, and is easier to work with inside Visual Studio 2010.
Additionally, keep in mind that C++ and C++/CLI are two different languages. For my first .Net project, I chose C++/CLI because I already knew C++, and this was a very bad idea: the learning curve from C++ to C++/CLI is similar to learning C# from C++: don't fall into that trap.