Well, what can i say about a book which allows a clever, carefull and insidous Dm to kill off his players with a whim!
As a DM for 2 years, i found my players starting to get a hand over me, they started thinking themselves better then I..so i bought this book and Obliterated the party Barbarian after he decided to "Take a peek in the chest"
Well anyway, The book is amazingly handy for both old and new Dms, It offers a good selection of new ways to play our Dungeons and also gives advice for designing your own little tricks and traps.
Howver this is obviously not a book for Players, After all theres only fun in something if there is not a challenge.
In general The book is Handy and rewarding a must but for Any serious Dm