The main selling point of a language such as XAML is that it can be read and written by both developers and designers. Oddly enough, every situation I've personally seen has involved the developer being the designer. This strays from the vision Microsoft set forth for XAML.
Luckily, I work with designers on a daily basis, and for an experiment I'm going to pick up a small side project with my designer. She'll be equipped with only Expression Blend and her image editting tools. I will be equipped with only Visual Studio 2008. Together, we will design, build, and prettify a working application.
Step 1 of the experiment is to convince my designer to do the experiment with me. Let's hope step 1 is a success! Any opinions for small apps we could build?