I was very intrigued by the "lines of death" which seemed to make the point that the risk of death had a spatial correlation: specifically, that the death risk for male smokers was higher in northern hemisphere (above the line), primarily developed countries, as compared to the southern hemisphere, mostly developing nations.
I find that somewhat counter-intuitive but in a fascinating book like this, that brings together both scientific, psychological and societal commentary, I was expecting to learn new things.
Looking at the legend, the red areas were regions in which deaths from tobacco use accounted for over 25% of "total deaths among men and women over 35". This explained some, as perhaps there were more reasons to die (warfare, other diseases, mine accidents, etc.) in developing nations than in developed nations, or that they had larger populations (so more deaths even at lower rates).
Did they mean 25% of the dead middle-aged people die from smoking? Or 25% of all middle-aged folks die from smoking? A gigantic difference!
Percentages are very tricky things to use. Every time I see a percentage, the first thing I ask is what is the base population. Here, the baseline appeared to have gotten lost in translation.
This set of maps also shows the peril of focusing too much on entertainment value, and losing the plot.
For those concerned about the effect of smoking on our society and our children, I highly recommend Dr. Rabinoff's highly readable new book, "Ending the tobacco holocaust". It contains lots of interesting tidbits and really brings together every cogent argument that exists, including the common ones you've heard and others you haven't.