As of today, the Windows Management Framework (WMF) 4.0 Preview download has become available on Connect.
This includes:

• Windows PowerShell
• Windows PowerShell ISE
• Windows PowerShell Web Services (Management OData IIS Extension)
• Windows Remote Management (WinRM)
• Windows Management Infrastructure (WMI)
• Windows PowerShell Desired State Configuration (DSC)

All functionality that’s available in Windows Management Framework 4.0 Preview is equivalent to the functionality found in Windows 8.1 Preview and Windows Server 2012 R2 Preview.
Now here are the Release Notes and personally I’m very glad Microsoft has released an additional guide for Desired State Configuration.

WMF 4.0 Preview can be installed on the following Operating Systems:

• Windows 7 SP1
• Windows Server 2008 R2 SP1
• Windows Server 2012

Wait… what? There isn’t a Windows 8 installation?
No, use the Windows 8.1 Preview.