I want Windows Forms Designer for F# (F Sharp) - Windows Forms is NOT deprecated, you was wrong in 2011.
I posted this idea in 2011 and the answer as:
"WinForms is deprecated, so there are no plans to create a designer for F#."
Now is 2015, and as you can see you was wrong, Windows Forms is alive and well.
Gauthier Segay commented
Some evidences this could be achieved: there was a winforms and wpf designer for ironpython documented as a SDK sample for Visual Studio:
MS Cambridge was looking for internship to do this: