Well written and aimed at professional programmers. I wish had ordered this book before trying to find my way through the countless online tutorials and forum posts. The book shows advanced Qt implementations. If you are after an easy entry to Qt this book is NOT for you, if you have already some experience in Qt or other interface programming SDKs (.Net, Windows Forms, MFC, ATL/WTL ... etc ) then this book is for you.
This is one of those useful books (manuals) that, by dipping in and treating each section as a tutorial both refreshes the grey parts that have long been disconnected/lost but, importantly, inspires you to refactor your legacy code/knowledge. As a, hoped for bonus, it leads to a lot more inspiration.