Another new feature supporting the WPF-Silverlight continuum is the VisualStateManager, which introduces a simple new way to apply visual states to controls. This mechanism provides a way to easily customize both the look and feel of a control by providing the means to map the control logic to its respective start and end visual states.

Figure 12

VSM is very flexible in that it automatically generates the transition animations in between the respective states, so the control author spends less time writing code and more time on the visual states that are defined in a control template. That means VSM can give a control author the ability to easily interchange the look and feel of controls, and VSM gives the control author a way to easily interchange how a control visually responds to user interaction.  This is fully supported with Expression Blend.