Nominally about woodworking, but mostly about how in love Offerman is with his own voice, which I find very hard to enjoy. If you already like him, though, you may fare better.
Offerman's outlook on woodworking is remarkable for how absolutely perfectly it falls in lock-step with current Internet popular opinion (hand tools make you a better person but they're too hard for normal people, SawStop is great, dominoes are amazing and not just an expensive way to recreate Ikea furniture, Lie-Nielsen and Veritas make the best hand tools on the market today, slabs are beautiful, &c.—not all wrong, but all very fashionable), but they're convincingly not the opinions of someone who only likes the look of a tool rack over a workbench, or of someone who only picked up the hobby last week. (They could be those of someone who picked it up three months ago and spent a lot of time watching Youtube videos since, though, and some of them are slightly surprising in a person who has apparently been doing it for multiple decades.)
The bulk of the book is projects executed and described by employees and hangers-on (including a brother and a father) of the Offerman Woodshop, plus profiles of people who are or were important to Offerman's woodworking in other ways.
The most striking thing about the projects is how damned expensive the tools used to make them are—whenever there are two ways to do a thing, OWS discards both and finds a more expensive way still—but they're possible to recreate if you're a normal person. Most of them ``aren't woodworking'' in that they involve no wood joinery whatsoever (a bottle-opener, a pencil holder, a canoe paddle, a lamp, a cribbage board) or only screws or dowel joints (a wooden kazoo, a birdhouse), but the usual cast is here as well: a stool with wedged through-tenons, a side table, a dinner table (slab, of course), a very nice dining chair, and a bed (which exhibits by far the highest level of craftsmanship of any of them, though I'm not convinced the knock-down joints are actually strong enough to hold up—and I say this as someone who isn't particularly a sex-haver).
None of the designs commit any grave sins against woodworking, which is more than can be said of many books that are fully about furniture-making, but I wouldn't say they're necessarily worth buying the book for.
Ultimately, if woodworking is all you're interested in, you'll probably be annoyed or bored for most of the book, because woodworking isn't really the point. If Nick Offerman is all you're interested in, though, you may still be bored by all the woodworking content. In the end, I don't think this book is really for anyone other than the many people in it.
It's hard to blame Offerman for it, though; if I could get away with it, I'd do the same thing.