"Truly underwhelmed"
Never.
The quality of the writing was just exceptionally poor. Every paragraph was finished with a pseudo-witty tag line ("Way to go boys." "Now we're talking.") that sounded like the authors really wished the book could have been a snappy Cosmo article instead. It made for tedious listening.
The authors seemed exceptionally pleased with their own wit.
Annoyance. The authors' claim (that lifelong monogamy is NOT genetically encoded in al humans for millions of years) is utterly non-controversial in both science and culture today. Nonetheless, the authors pretend that pretty much everyone believes the opposite. They proceed to restate the opposite case in the most extreme and laughable terms (drawing on sources back to the 19th century for evidence of current thought). Having stated the other side in laughable terms, they never actually bother to prove their own case; they simply mock the other side and then list any evidence available for their own perspective without delving into any of the complexities of teasing out something as subtle as sexuality from the archeological and anthropological record.
Looking back, I suspect I bought this book because it had sex in the title. Having read it, I now feel a little dirty and ashamed for taking part in such a shallow enterprise.
"Flawed"
Sadly this is not Weatherford's best work. The title itself is plain odd, given that his first chapter focuses on the silver mines of Potosi and Zacatecas. Just to be clear, the sliver was not a "gift" of the Indians, millions of Indians were forced into the mines at gun- and swordpoint and worked to death. That's slavery, not a gift.
However, the real flaw is that Weatherford simply tries to hard. He seems unable trace the historical connections and cross-currents without drawing extreme and absurd conclusions. New World food products were and are very important around the world, but his claim that without the potato, the two world wars wouldn't have happened is as unprovable as it is absurd. Likewise, his claim that Machu Picchu was an agricultural research station is utterly without foundation, and just highlights his desperation to seize on any claim to support his conclusions.
It's a pity, because the subject matter is interesting, and there are plenty of connections and influence of Indian/New World products and idea that a general reader may not know. The over-the-top claims, however, damage the whole work. For a more thoughtful treatment of the same topic, readers might try Charles Mann's 1493.
"Painful to listen"
I could not get more than a couple of chapters into this. The narrator is truly awful, and makes the entire book unlistenable. It's a shame, because the subject is very interesting.\
"Good facts, weak story"
The author is clearly knowledgeable about the modern oil industry; there were plenty of facts in the book I did not know. However, the book fails in three regards. First, the author displays little understanding of the context of events outside of specific oil-related news. His analysis rarely goes beyond the headline level, and contains no discussion of different perspectives on and reasons for events. Second, the author cherry picks sources to make his point. For instance, his certainty that the Iraq War was based on WMDs rather than, say, oil, is back up by sources ranging from George W. Bush to... Laura Bush. Evidence that Iran is building nuclear weapons is provided by "some Arabs say." Finally, the book has no actual story to it. Each chapter deals independently with a facet of or event in modern oil history, with no connection or even transition between them. As such, there is no story to follow.
Thus, the book is good on its oil facts, but poor on context, explanation and story.