i recently saw some videos on F#. it seems it used mainly for Service or Classes only? i see no \"F# WPF\" app in VS2010 Beta?
Of course you can use all the WPF classes from F#, too. You can create Windows, controls and everything else from F# and I also sometimes use it from the F# console.
It's not as tightly integrated into Visual Studio as C# or VB yet, but as you can see in the comments, designer support in the future is feasible. I guess we'll have to wait until then (or use other tools).