It sounds like Google wants to get more edge compute in people's homes so they have a new vector to deploy AI products on, but they're still so far from actually deploying an innovative product that they can't announce anything to actually drive up hype.
Then, the rebranding is only because they've abandoned the original "minimal footprint" ethos of ChromeCast.
For curiosity: Understanding Digital Signal Processing, by Richard G Lyons. I read it when I was starting college as an undeclared major, and I honestly didn't understand half of it, but I was getting into music production and it taught me the ins and outs of impulse responses. I later declared a major in Applied Computational Math primarily because of that book.
For intellectual ability: it wasn't a particular book, but it was an honors-level Real Analysis class that forced me to re-learn the way I learn mathematics.