Despite the fact that Tolle claims to have written this book only upon request from other people, this man, like so many others, seems to have the mission of convincing the world that what worked for him must be the solution to all earthly problems.
Anyhow Tolle's analysis and "method" of getting to the Now is quite powerful, helpful and can in fact change your life to the better.
However, Tolle having found this new focus point in the prsence, now falls into the trap of making it the center of a world view, overly generalizing the results and judging everything from this/his newly aquired standpoint.
He is quick to draw "obvious" conclusions, quote from every monumental book our civilization has brought forth (the Bible, the Koran, the Tao, etc.) and interpreting the quotes within a paragraph in the light or as a proof of the "power of now".
And, like many converts, who have lived through a dramatic turning point in their lives, he is very willing to condemn everything else, and especially everything which actually correlates with his "previous" life, as insane or mad.
This book carries a great message but you will have to be careful to draw your own conclusions and discern the basic truths from the personal problems, which are mainly related to the Tolle-Personality rather than yourself.