You might check out the series by Don Syme on F# where he demo's creating a gui. the following link is to third part of the series (you can link from there to the other two parts).
Using F# for WPF development would be a very interesting GUI paradigm...
http://channel9.msdn.com/shows/Going+Deep/C9-Lectures-Dr-Don-Syme-Introduction-to-F-3-of-3/
