So there’s a thing about spoilers, which is that they impact different works differently. If I tell you that Eddings’ Belgariad is the story of a young farmboy who is to fulfill an ancient prophecy, I’m technically giving you information that you wouldn’t have until well into the first book, and spoiling some big reveals. But practically speaking, that’s all such genre furniture that anyone above the age of twelve already knows the general shape of the book before they start reading, and you can only really spoil it by giving away the fates of individual characters or specific events from late in the book.
But Neal Stephenson’s Seveneves is a different thing entirely. It’s a book whose shape is not immediately obvious, which doesn’t fall into standard genre patterns, and which deserves to be read as a completely blank slate.
This is apparently a belief that the publisher doesn’t share—if you read the description of the book on its Amazon page (or, I assume, on the cover of the printed-out-and-glued-together version), it blithely tells you just about everything that happens in the book, in a way that will make reading it a much less interesting experience. So take my advice and don’t read that description, or anything else that anyone’s going to say about the book, because I can pretty much guarantee that they will all be laden with spoilers in a way that you really don’t want.
And since, if you’re going to listen to me, this is the only thing you’ll ever read about Seveneves until after you’ve finished it, I’ll give you the information you need to decide whether you should read the book.
First, as to what it’s about… well, I think I can safely say that even by my lights, it’s not a spoiler to quote the first sentence: “The moon blew up without warning and for no apparent reason.” The rest of the novel follows from there, and beyond that you shouldn’t know.
Second, as to whether I’d recommend it: Yes, absolutely, it’s very good. It’s not quite Stephenson at his best, at the level of the Baroque Cycle or Anathem, but it’s not a trifle like Reamde, either. It’s a major work from a major author, the kind of thing I expect to see on award ballots. If you like SF or Stephenson’s other works, you should read Seveneves.