Troubling starting new silverlight 4.0 project (in f#) from VS2010

I am trying to protoype a silverlight 4.0 project using F#, and am having issues getting it to install... the silverlight 4开发者_如何学C tools for Visual Studio 2010 is barking at me:

Installation Requirements:

Visual Studio 2010 or Visual Web Developer Express 2010 or Visual Phone Developer Express 2010 that matches the language version of Silverlight Tools 4 must be installed before installation of Silverlight Tools can continue. Silverlight Tools is available in other languages at http://go.microsoft.com/fwlink/?LinkId=177432.

VS INfo

Microsoft Visual Studio 2010 Version 10.0.30128.1 RC1Rel Microsoft .NET Framework Version 4.0.30128 RC1Rel

Installed Version: Professional

Microsoft Visual F# 2010

01018-315-4422943-70575 Microsoft Visual F# 2010

Thank you in advance

F# for Silverlight 4 is not out yet (though I think it is coming fairly soon). For the moment you can only use F# for Silverlight 3.

EDIT (May 17, 2010)

The new Silverlight tools are released, go here and get an install including FSharp.Core.dll for Silverlight 4.

See also this blog for a short step-by-step walkthrough.