Posted by: Richard Siddaway
The PowerShell team have been updating the online help files since PowerShell v2 was released. Unfortunately your local help files haven’t been updated. This now changes with the release of a CHM file containing the updated help files – http://blogs.msdn.com/b/powershell/archive/2011/05/17/download-the-updated-core-help-chm.aspx
This won’t update the files you access through get help but it does give access to the up to date information.