The Microsoft Silverlight 4 Beta Client for Facebook has been released as a developer preview sample. In order to use it you must have Silverlight 4 developer builds installed. There is a sample application which does the same things you can do when using Facebook web version. There are a lot of cool ways to explore your Facebook information. It supports some kind of Outlook integration – if you right-click on events that you may have to send an email and such.
You can download the application and try it yourself. It can also be intalled on Mac but only if Intel is inside. Enjoy! 🙂