Here is a pointer to an Introduction To the Exchange Management Shell: http://download.microsoft.com/download/6/d/4/6d4b5c51-dd72-41d3-b5b1-9dc22b1d35f1/IntroExchangeMgmtShell.pdf
This is a nice glossy view of the important aspects of both Windows PowerShell and Exchange’s use of it.
PSMDTAG:FAQ: How does the Exchange Management Shell relate to WIndows PowerShell? ANSWER – The Exchange management Shell is built upon Windows PowerShell.
The Exchange team has been a fantastic partner for V1.0 of PowerShell and done a great job showing everyone a glimpse of the future where all Admin GUIs are layered on top of Command line interfaces. Its a superstar team, its a superstar product.
You can get a quick-reference guide for the Exchange Management Shell at: http://go.microsoft.com/fwlink/?LinkId=64647
Jeffrey Snover [MSFT]
Windows PowerShell/Aspen Architect
Visit the Windows PowerShell Team blog at: http://blogs.msdn.com/PowerShell
Visit the Windows PowerShell ScriptCenter at: http://www.microsoft.com/technet/scriptcenter/hubs/msh.mspx
PSMDTAG:Exchange: Exchange Management Shell