Here’s my 2nd article on WinRT with C++.
Databinding (at the moment) is easier with C# or VB than with C++ since with C#/VB, the .NET interop handles the required plumbing required to get databinding working. With C++, the required interfaces and functionality need to manually implemented (which is what the article covers). I personally hope that this will change in a future release and the compiler will generate this code for us automatically. So the article is mostly of academic interest specially if you are interested in knowing how databinding is implemented at the consuming client level (not the Xaml internals).