The long term goal is to have native clients for all major platforms. We started with Windows as it is the one platform that needed a more secure client the most. Sadly Windows doesn't have the best choice of UI APIs after we elminated Qt for various reasons. A pure win32 interface is being worked on and will yield a much leaner client, though it will take a lot more time.

Also note that our target user likely doesn't know or care what .Net is.