I debated between 3 and 4 stars on this one. Ultimately the book was just not to my taste and so I gave it a 3 star rating.
I have not read many Japanese authors and so, part of my liking for this novel was the novelty of the Japanese style. At times in pacing, tone, and the way the author revealed things it reminded me to Kazuro's Never Let Me Go (which I enjoyed more than this book overall).
In general I found it too repetitious; oftentimes the author would spend 15 pages describing something and then later in the novel (sometimes even just a few pages later) give a few paragraph summary of what had been said. I wasn't sure if Murakami was trying to be helpful (remind the reader) or if he was just padding his pages, but either way it annoyed me.
The tone (especially in conversations) at times, reminded me of a video game (when the character that you go up to just simply tells you what is necessary to move things forward without any subtlety). I found it stiff and unrealistic (not that this is a realistic novel) that people would say things the way they say them in this novel. I'm not sure if Japanese culture is that straightforward (a great example of this is when Ayumi and Aoumame first meet in the bar and they literally say directly to each other, "Hey I'm here to find random men and have sex, aren't you? Do we want to do it together?" In America, this type of conversation is much more subtle; certainly there is some ethnomethodology at work in which people understand each other's motivations without having to explicitly state them.) In this novel I would guesstimate that at least 60% of the conversations between characters felt too blatant, contrived, and lacked any of the subtlety that would occur in natural conversation.
Overall it is a fantasy novel and therefore I shouldn't hold it to any sort of realism, but I found the characters way too accepting of strange occurrences and their intuition too conveniently accurate. Really, Aomame discovers there are now two moons and that she didn't notice some items in the newspaper that occurred a few years back and she immediately assumes she has jumped to a parallel universe. Similarly, Ishikawa understands exactly the relationship between Fuka-Eri, Tengo, and Aomame...it just feels too contrived.
The characters themselves were oftentimes one-dimensional and were simply moving in ways they had to move according to the over-arching structure of the 1Q84 world (meaning the novel, not the world within the novel). I think Murakami's reviews of Air Chrysalis were informative of the ways in which he wanted his novel to be received/reviewed.
My last complaint was with the structure; the first two-thirds of the novel are written with alternating chapters between Aomame and Tengo. For the final section, Murakami adds Ishikawa's perspective. I understand the convenience (again) of this tool; he can much more easily explain the interactions and workings of Sakigawa by introducing Ishikawa as a main character, but it felt again like a convenient cop-out.
On the plus side, the story was compelling and the style was different that what I am used to reading.