Using Expressions Blend with Visual Studio 2008
Expressions and Visual Studio 2008 are tightly connected, you use Expressions Blend to modify the appearance of the project and then you are able to open the XAML in Visual Studio 2008. This allows you to work with the XAML code directly within the programming environment. Take a look this brief video to see just how easy it is to work with the design tools.
Here is a diagram of what is going on between Expressions and Visual Studio 2008 (this is an image in a 2 column table):