The book traces the history of everyday practices and artefacts (such as toothbrush/dental care, beer, clock/measuring of time, beds etc.), built around a framing story of spending a Saturday from waking to going to bed.
Thus, the book has an organizing timeline, with the help of which the author discusses quite a number of "thematic case histories" of "how things developed to be as they currently are."
Was it good?
The big idea of the book is very fascinating: really pondering, for example, why our clocks seem and work as they do (e.g. why there are 60 minutes in an hour). The "thematic case histories" are well chosen and discuss -- at least to me -- quite interesting issues and historical developments.
On the other hand, however, the writing style is from time to time quite irritating -- that is, again, to me. For example:
"This, of course, finally led to the English alphabet of 26 letters, which I am currently using to bore you to tears. Sorry about that. Anyway, to make it really simple, without the Phoenicians there would be no 'Alphabet Song' on Sesame Street, and I think we can all agree that would've been a tragedy."
Thus, if the book would have been written in a more neutral, factual style (or more mindfully humorous), I would have enjoyed even more.
The main take-away for me?
I was quite astonished as to how advanced the ancient Roman and Greek civilizations were in terms of technology. For example, their centralized and public water and sanitation services and technologies -- already some 2000 years ago -- allowed for water on the tap and variously heated swimming pools in public baths. Thus, human ingenuity has flourished for a very, very long time already.
Who should read the book?
I think that the book is of quite general interest, but the writing style is off-putting to such a degree, that I would recommend the book only if the subject matter seems highly appealing to you.
The book on Amazon.com: A million years in a day