Timequake is Kurt Vonnegut's last novel. Vonnegut himself is the narrator, alternating between personal anecdotes, descriptions of the process of writing Timequake, and scenes from the timequake and the last few years of Kilgore Trout's life. A Timequake is a brief contraction of the universe, that causes a preceding interval of time (in this case 10 years) to be played over again, exactly as it had been before. Except everyone has their memories of the last time round.
Timequake is one of the two post-Breakfast of Champions novels I'd recommend to anyone who isn't a die-hard Vonnegut fan (the other is Galápagos). Vonnegut's career is interesting because there is a very clear midway point (or perhaps an apexe) in the form of Breakfast of Champions (1973). It was around this time that he published his last short story, "The Big Space Fuck" in the Harlan Ellison edited anthology Again, Dangerous Visions (1972). If you're familiar with the ending of Breakfast, it isn't that surprising. Technically, stylistically, and philosophically, his first six novels all built up to Breakfast of Champions. His remaining novels, even the ones I recommended at the beginning of this paragraph, fit into an identical mould.
For one, the characters are all completely passive. While this is true of his earlier novels, it's taken to a new extreme in his later. As Vonnegut himself advised "Every character needs to want something, even if it is just a glass of water." Generally speaking, his later protagonist/narrators don't even want that. They just want to be left alone, but not badly enough to do anything about it. Additionally, the format of the novels is 'written record left by the protagonist.' This is not inherently bad (cf. Mother Night and Cat's Cradle), but it just retreads a lot of the same ground. The structure of the novels is the same as well, a non-chronological cycling back and forth between the time of the character's writing the story and the events narrated, each time adding a little more while constantly hinting at some mystery/cataclysm just over the horizon (e.g. what's in Bluebeard's shed? What happened to Midland? Why was he arrested? etc.). Galápagos and Timequake succeed despite this, the former because of an clever and engaging premise, the latter because Vonnegut can be at his best when he writes about himself.
While I would still recommend any of the first seven novels to Timequake, it's definitely worth a read if you have a copy lying around.