I checked this book out of the library recently, and most of the information in it pretty much fits into my models even if the specifics are news to me. I was quite surprised though, to find that Warren Buffett in particular directs his holdings to a lot of deliberate competition stifling and price gouging on captive customers. I had gotten used to thinking of him as the Big Good of the investment world, and I was surprised to realize that even if he puts his own personal fortune to benevolent uses, he doesn't have any particular qualms about deliberately concentrating wealth rather than producing it, in order to maximize profits. That didn't reflect the traditional capitalist values I imagined him to hold.
Information that surprises you is interesting as it exposes where you have been miscalibrated, and allows you to correct for that.
I suspect the users of LessWrong have fairly similar beliefs, so it is probable that information that has surprised you would surprise others here, so it would be useful for them if you shared them.
Example: In a discussion with a friend recently I realised I had massively miscalibrated on the percentage of the UK population who shared my beliefs on certain subjects, in general the population was far more conservative than I had expected.
In retrospect I was assuming my own personal experience was more representative than it was, even when attempting to correct for that.