Douglas Finke is an MVP for Windows PowerShell. This one point is enough to say the quality of this book.
When I was started learning and writing Powershell scripts, I really got crazy about that. It has elegant syntax which will impress both developers and administrators. Powershell is not just for Administrator. This book is for developer. The first 10 chapters cover the following different aspects:
- Quick introduction
- text template transformation
- Powershell in UI
- Domain specific language using PS
- Net.Webclient and Powershell
The Chapter 11 covers Powershell 3.0.
The content is concise and clear. Every chapters taking you in different level.
For beginners, “Getting Started” and “The Dime Tour” covers PowerShell basics. This will give you different introduction to the developers, but not at the basic level.
Otherwise, every chapters will impress you like writing “Ruby” script in Linux world. 
If you are a .NET developers, then this would also be in your book shelve in near feature.
Purchase this book at http://shop.oreilly.com/product/0636920024491.do