Just finished Book 3 of 1Q84. Loved it. Different from Books 1 & 2 - it reads more like a thriller, a cat and mouse chase, as the net is closing in on Tengo and Aomame. Also, a much more straightforward story - yes, there are still "Little People" lurking about, and air chrysalises being woven, but the reader knows what's going on, by and large. Let me warn you that it's not a happy ending for everybody. One of the characters that I had grown quite fond of dies a horrible death - enough said.
A few loose ends that I would have liked to see resolved/explained - who exactly was the dowager, how did she know about Sakigake? Was the Fuka-Eri that Tengo knew a "maza" or a "dohta" - she seemed different in Book3?
But it didn't stop my enjoyment - once I like the characters, I'll keep on reading, and cheering them on.
BTW, if you're puzzled by the terms maza and dohta, read this blog review. The blogger didn't like 1Q84 so much, but she makes interesting comments. If you like her style, read this post of hers "Life with a Japanese man" or "The ninja and the dinosaur in the station".