I'll admit to not having high expectations for this book; after all, it is only 128 pages long. Unfortunately, it was really disappointing. There just simply is not enough insightful information here to make it really interesting.
The goal of the book is to look at some of the more ridiculous predictions of the future made throughout history, from giant "land submarines" to jetpacks. But there are two big problems with how the authors treat this subject. The first is that their approach is very superficial--they touch on each subject quickly and then abandon it, rather than grouping them together in weightier themes. It's like eating finger foods, each bite is unsatisfying. Some of these subjects, like mega-cities or massive vehicles, also deserve a deeper discussion. Instead, the authors assert that (paraphrasing) "things are gigantic when times are good" and mention the dinosaurs and large prehistoric insects. That's a rather odd and imprecise statement to make, and although it might apply to biological entities, it doesn't necessarily apply to manmade objects. What about computers? Why are they getting smaller? And are big things naturally "good"?
The other major problem is a startling lack of dates. Photographs, magazine illustrations and diagrams are frequently presented without _any_ indication of when they were made. Is this illustration from the 1950s or the Depression-era 1930s? Isn't that relevant to why it might have been produced? Many of the pulp magazine covers are cropped in such a way that the dates are cut off, which is incredibly annoying. Thus, the book reads like a haphazzardly arranged scrapbook, without any keen insights about how or why people might make erroneous predictions about the future.