Another pretty quick listen, and the first that really captured my imagination. The story itself was fine, if not particularly exciting, but the world they end up struck a chord with my imagination and got me thinking a lot.
After the events in the last book, the crew ends up on a planet presumably inhabitated by nothing but retroverts, organized into their own nation's. We see only 3, but I assume there are many others and plenty of other similar worlds with other takes. Of the retroverts we see New Cali, where everyone uses technology and culture appropriate to the mid (20th) century California, New Camelot, where it's some weird medieval time period, and a non-specific ancient Asian Empire.
What got me thinking wasn't the specifics of the hijinks on the planet, but the planet itself and what would drive people to go live there. Thinking about it, though, it seems obvious. With trillions of people in ARGO, and what are likely hundreds of planets to choose from, how do decide where to live, and what to do? The answer definitely seems to be more and more extreme specialization, to the point that reenactment communities turn into entire planets.
The thing that captured my mind, though, is what this means for everyone else. Assuming that transportation is relatively easy, which it seems to be, it would mean that something like a simple job posting likely gets hundreds of thousands of applicants. You'd likely see extreme stratification, since employers could easily throw away all but the 0.1% most qualified applicants, and only talk to them. But those applicants almost certainly have hundreds of similar top tier employers after them, causing a bidding war for every employee, at least if you make it in that slot.
Really, it's a fun story, and it got me thinking just how different things would look if there were 1000x more people just around us at all time.