I first mentioned The Dark Visitor in my article "Collection of information on Cyberwarfare and the recent targeted attacks (updated)". The Dark Visitor was a book suggested by my friend Maarten. The Dark Visitor is not only a book on the World of Chinese hackers. They also have an excellent blog with their hacker glossary and a list of top Chinese hacker.
The Dark Visitor was also the one who discovered the call for the DDoS on CNN.COM and warned us about it. The blog is regularity updated with all sorts of useful information. Now it has only become better. They started their first podcast!!! Go and download nr.1 !!!