A later update. I'm downgrading this to 4.5 ⭐. Thinking back, there are too many passages that are clumsy or unfinished threads to be a true five ⭐. It's still been my best read of this year, though.
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Wow. What a ride. Absolutely the best book I have read this year.
I am fairly.new to to Stephenson, having read only "Snowcrash" from him before this, but I am certainly going to seek out more of him after this. The multi-threaded creative detail in this rivals AS Byatt's "Possession", but is more accessible and a lot funnier.