Expression Blend 4 makes it easier than ever to design your WPF and Silverlight apps. Here are the official bullet points:
Particularly impressive to me is the SketchFlow feature, which enables rapid prototyping for your WPF and Silverlight applications.
SketchFlow prototypes are actual WPF or Silverlight projects, so once your design is finalized, you can choose how much of the prototype you want to reuse.
And you can use Expression Blend 4 to design apps for Windows Phone 7. Imagine your Silverlight applications lighting up in the mobile world.
Download the 60-day free trial and leverage the power of WPF and Silverlight in fun new ways.