I'll admit, the book hangs out on the lower eschelons of my 4 star, but I don't dislike it enough for a mere "it was alright". It was a good book, containing things that I look for in most modern fiction - diversity on just about every level, lack of needless rape scenes, etc.
Initially what threw me was the creation of Amberlough itself. I think what knocked me a little off kilter was the fact that it's not a particularly fantastical world - in fact it's not at all. There's no magic or scifi or anything especially out of the norm for the 1920s. So I was confused as to why Amberlough had to exist at all - why not just make a period piece? Almost all of the more "alternative" aspects of the piece, the fact that non-straight people EXIST, goodness, could have been excused as the seedy underbellies. As the book continued to coalesce Amberlough, however, I did begin to realize how impossible it was. Amberlough's political shifts and disputes are unique to Amberlough. Other than making up a fictional European country for no reason, it's hard to affix the schemes of Amberlough to any country. Oh sure, there are parallels, the obvious being the Ospies, but the mixture that Donnelly has got going in Amberlough is unique. So Amberlough is a blanket covering the early 20th century, enough to see it through the folds, affixed to place by Donnelly's sharp and clever use of colloquialisms that are used in plain context so well that they never need definition.
However, because of Amberlough's introduction I'll admit to being a little befuddled for nearly the first quarter of the book before I got into the swing of things. Things were just slightly off to be frustrating, machinations already deep in the works when the story starts. But! As I got used to it, I began to appreciate it.
I desperately hope there's a sequel. I'm feeling a little Empire Strikes Back at it, except I don't know that a follow up is on the horizon. There are difficult decisions made, desperations exploited, stances taken. If that isn't the perfect way to start what is undoubtedly going to be an awesome sequel, I dunno what is.