I'm starting this post while i'm only halfway through the book.
Boneshaker is a kind of steampunk zombie apocalypse. It's set in an alternate history Seattle in the late 19th century or very early 20th century where a mad engineer created a giant steam powered excavation machine for mining in the Klondike, but on the initial "test" run it levels a large section of the city and breaks open some underground source of noxious "blight" gas which kills anyone who breathes it very long and then usually turns them into zombies. The city is evacuated and a giant wall is built around the city to contain the gas and keep it from spreading. Of course it wouldn't be much of a story if some people hadn't refused to leave and instead figured out how to live with the blight gas and the zombies.
(The confusion about the date is because the Civil War is still going on at the same time. It's mentioned that the war has been going on quite awhile, but i don't think an exact timespan was given. So either the Klondike rush happened a lot earlier, or the Civil War got started later and ran long, or the Civil War started on schedule and has been dragging on for about 50 years.)
As usual in a SF setting i have numerous thermodynamic issues with the zombies. However that is _always_ the case. Seanan McGuire did a far better job than most at rationalizing them but even she couldn't address all my concerns. It's just one of those things, if you're going to have a zombie story where the zombies stick around for awhile there are certain issues you're just going to have to ignore as a "gimmie."
However one plot point was handled exceptionally well i thought. I'm writing this before i've even finished half of the book just so i can honestly say i don't know the answer to this question so it isn't really a spoiler in my mind, but i'll put a cut just in case you don't want to know that the question is raised.
The engineer who apparently caused the whole disaster disappeared afterwards. Pretty early on it's revealed that there's a mad engineer who showed up in the city shortly after the disaster and set up shop providing useful inventions and seems to be leading one of the factions in the city. In a lot of books no one would think twice about the coincidence and everyone would be totally shocked when it was revealed at the end that it had been the same person all along.
In this case however, as soon as a significant amount of his history is revealed the person relating the tale pretty much says "yeah, i know what you're thinking. A lot of us are wondering it too." Apparently the new engineer will neither convincingly confirm nor deny that he's the same person as the old engineer. (I'm guessing that the possibility that he might be the same person adds a certain amount to his status, but if everyone _knew_ he was the same person they might feel compelled to lynch him, so...)
So a lot of people are pretty sure he's the same person based on the similarities and coincidence of timing, but one character who has secret knowledge about the old engineer is convinced they can't be the same person, but won't say why.
I love this because not only does it immediately get rid of the forehead slapping when the "twist ending" is revealed and you wonder how no one ever considered it, but it actually makes it so that it can be a twist ending whether they end up being the same person or not. I've got multiple theories running in my head about what the secret knowledge might be, and then another layer of multiple other theories about how that knowledge might be incorrect. And then of course a set of theories about who the new person is if he isn't the old person, albeit a much smaller set since "guy shows up in place, takes advantage of reputation of a guy who used to live there" really doesn't require that much in the way of explanation.
But anyways there's steampunk and zombies and airships and pirates (yes airship pirates, no zombie pirates or airship zombies, at least not yet) and a well done plot, what's not to like? (I will of course add an addendum to this when i've finished to confirm whether or not there is anything not to like =)
Non-spoilery addendum: The book continued to be good in the second half, but i'm not going to say anything about how the identity issue was resolved or how close my guesses were :)