By page 50 I was ready to return it. I really don't care for ersatz mythology — even the real stuff generally leaves me cold, making my adoration of Calasso's The Marriage of Cadmus and Harmony all the more surprising — and even the modern-day sections were seriously lacking in... I guess the word would be patter, as the language was something I had to fight through instead of reeling me in. But I stuck with it, and it grew on me; by page 150 I was actually reading with interest instead of just to have something to look at on the subway besides beer ads. Which isn't to say that it was necessarily all that great. But it was readable.
The basic premise is that a representative of a confederation of worlds, all of them, including the Earth, inhabited by offshoots of a proto-humanity, lands on the frigid planet of Gethen to recruit the inhabitants into the league. There are two countries on Gethen: the envoy tries first the monarchy, then the bureaucracy, then has to escape across the frozen wilderness back to the monarchy with the help of an exiled vizier. That's pretty much the entirety of the plot, the bulk of the story given over to sketching out a picture of life on Gethen, where it's really cold and where the people spend 5/6 of the time as androgynous neuters. (In practice, this seems to mean that they're guys whom the envoy occasionally finds a bit too limp-wristed for his tastes. Urgh.) The rest of the time they're "in kemmer," morphing into males or females (not necessarily the same one each time) and compelled to mate. But the book is not actually about this, at least not in the sense that it would be had Le Guin's approach been so reductionist as to make every aspect of Gethenian life revolve around their peculiar sexuality. It's just sort of there, and occasionally it comes up and a few pages are devoted to it, but there doesn't seem to be any sort of Message About the Meaning of Sex in the book. Which led me to wonder why the book was written. I thought, "Hmm, it's not a polemic... it's not plot for plot's sake, since there isn't much of one... it's certainly not about the characters, since they're all pretty thin..." and then I stopped. Hmm. Character pieces. I wrote a book a large part of whose point was to have readers spend some time with a bunch of characters who'd been floating around in my head; getting to know interesting people, I figured, was intrinsically valuable and enriching. Couldn't the same be true of interesting planets? There are plenty of real-life narratives that are about traveling to strange lands where the customs of the people there aren't metaphors and aren't meant to illustrate anything; is their only value as a heads-up as to what to expect should you find yourself in the area? Hardly. If nothing else, they point out elements of our society that we take for granted — in this case, stable gender — and make us actually think about them for a moment. So upon further reflection, to observe that this book presents an alien world not as a means to any particular end but rather as an end in itself is not itself a criticism. To observe that of all the fictional worlds I've encountered this is not one of the particularly enthralling ones is.