We have an important update regarding WMF 3.0 ("Windows Management Framework") compatibility. Those who want to install WMF 3.0 to take advantage of all the great features this update provides can do so by installing the update from the Microsoft Download Center, after reading the known compatibility issues detailed in the blog post below.

http://blogs.msdn.com/b/powershell/archive/2012/12/20/windows-management-framework-3-0-compatibility-update.aspx