I ran across this post from Jeffrey Palermo which mentions some tools for testing .NET Windows Forms (aka WinForms) applications. Since I will be working on a WinForms app, this could come in handy.
The latest tool is SharpRobo, by Vivek Singh. While Jeffrey Palermo says he wants to try using it with FIT, Vivek has a blog entry stating that he thinks FIT is too simplistic for defining tests at the UI level. He prefers using a full-strength programming language like Ruby.