The concept and value of a single numeric score (IQ) to measure your mind's ability is disturbing, and inaccurate for almost all purposes.
However, I'm not saying we should reject testing.
It would be interesting to devise a test that gave you scores on some number (20?) of important attributes for success, and then predict for you what careers will most leverage your strengths while not depending on any of your negatives.
Of course this test and career matrix would only be useful if it were scientifically tested for accuracy.
A Mind at a Time is a promising book, dividing the mind into eight areas and telling parents and educators to not treat all children the same, etc. But I was disappointed in the lack of scientific validation for the application utility of different profiles.
Oliver Sacks is a wonderful author who explores extreme differences of abilities in the minds of his patients.
Emotional Intelligence has been called the "EQ" book, showing how your ability to connect with other people will predict more success than a raw IQ score. One of my favorite stories in this book is the marshmallow test.
The Mismeasure of Man by Stephen Jay Gould is recommended by Karl. (I've ordered but not read it yet...)