Mandell uses the terms 'being in the Now' and 'I am' to describe the results of her Self-Powerment. But I found her book shallow, busy, and devoid of the simplicity, silence and presence that pervades the writing of Tolle and others who actually experience what Mandell aspires to.
She has an okay premise: When you suppress emotions they discharge by piggybacking onto thoughts. This is nothing new. She uses analysis of the structure of language to determine just which emotion is suppressed: Are you thinking/talking of the future? Then you are experiencing fear and you have suppressed anxiety. She further believes that basic emotions of anxiety, frustration, and disappointment are valuable to tell you what to do for survival. So once you identify the emotion at the basis of your thinking, she suggests you act on it to remove the source of the emotion/danger. What if you're chronically anxious because of past trauma? No answers here.
She has one good and useful idea: If you are anxious, fearful, sad, frustrated, etc., put your attention on the body/feeling sensation of the emotion. This is not a new concept, and is not stated clearly or succintly in her book. However, if you do this, you will find it withdraws your attention from the loop of thinking and your mind will settle. There, you have the best part of the book.
As a practise her book advocates monitoring your speech and thought patterns to find which emotion you're suppressing and making charts of the results.
If you like to feel in control through analysing and making charts, you will like this book. If you'd rather just be free, I suggest Byron Katie's Loving What Is or Hale Dwoskin's The Sedona Method.