Took me a while, I admit (even though they were chapters I've skimmed through quickly).
First important point about this book: it's really **in depth**.
Well, author is not decompiling Powershell on his own :), but he covers some topics I've never seen covered in any other PowerShell book.
For instance:
* details of remoting
* good description of how credentials work in PS
* CIM (it's not that different from WMI, but it's still good to learn the diffs)
* DSC (brief description, but unlike to some other books - it covers & emphasizes some very valid points)
* Workflows (ok, I think they are useless ;P but now I have a better basis to claim that)
Neither time, nor money wasted.
Why 4 & not 5 stars then?
Some code samples were very easy-going, debugging chapter has disappointed me a lot, chapters like GUI/DB one doesn't make much sense TBH (it's about using .NET classes, so why bother?).
Anyway - if you want to refresh your Powershell-fu, this book is quite a good choice.