This is still the authorative book on single Chinese herbs. However, Chinese herbs are nearly always combined into formulas, and Bensky has another equally huge book on that topic. These two books are medical references for licensed acupuncturists (who are Chinese herbalists), and NOT for the casual reader or layperson to medicate themselves. You won't be able to properly apply the information in these two books without first learning Chinese medical diagnosis - the right medicine must follow from an accurate diagnosis.
The tragedies and legislation concerning ephedra illustrate that laypeople will not neccesarily use herbs traditionally, or safely.
Most traditional acupuncturists in the West attend 4 year schools, and more than 900 hours of herbal medicine are included in their training. I would suggest, if you want to avail yourself of the power of Chinese herbal medicine, that you see one of them.
If you're looking for a more practical layperson's introduction to Chinese herbs, check out David Molony's, or Jake Fratkin's books. Another good one is Henry Lu's book on combining Chinese herbs with foods to balance your patterns of imbalance.