The quality of a factual book should be judged by its lack of overt partiality, comprehensiveness, sources and ability to make you think and ask questions. This book scores well on all points and above all reads like an essay which you can zap through. It contains a good bibliography for follow up reading and includes details of the the award winning "Journal of Buddhist ethics" on the web which was partly established by the author. Apart from the author's erudition his book is backed up by other experts and has been reviewed by his students.
Above all the book analyses what is meant by religion (as Buddhism does not easily fit this classification) and provides a modern interpretation of this system of thought from all its major perspectives. The treatment of Mahayana Buddhism short, yet precise and on the whole Keown concentrates on highlights. Towards the end is a discussion on Buddhism in the West. The book also provides useful comparisons with other religions.
Compared to many small and "cheap" introductions to Buddhism, this book is fairly impeccable. It is not perfect (2 tiny errors I identified with regards to scriptural quotations) but will lead anyone interested to work out what Buddhism is for him or herself, rather than being spoon fed as it were. I was however, disappointed that the book ended so fast - and glad at the follow up leads left, by this trustworthy writer.