Before diving into this, I did not want multiple XAML pages and chain them together. I wanted to use some of the built in behaviors and states and use no procedural code.
You may want to see a demo of this live before reading further. You can check it out here: http://mbcrump.web01.appliedi-labs.net/fadein/Default.html
To get started, we will create a new Silverlight 4 application using Expression Blend 4. After we create the application, we will add 2 buttons and it will look like the following. Pretty simple right? I went ahead and added names and a background color but this is completely optional.

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