If you want to read my full spoilerless review, check out my blog here.
Disclaimer: I read this in Japanese and not in English, obviously, so my understanding of the book only goes as far as my understanding of the Japanese language.
Good to know every writer for anything Digimon Adventure related only have about two or three unique ideas collectively. While Kizuna does a better job of telling the same "but being adults is scary" story than Tri and does manage to make it more emotional, Kizuna unfortunately falls flat because there's nothing that happens that hasn't happened in any of the Adventure movies before. The ending and overall threat falls flat and loses any meaning because, in general, we know what happens in the future due to the 02 epilogue, making the entire journey fairly meaningless.
I wish I could give this 2.5 stars because I feel that 2 stars is a little harsh as there were parts of the book that got me emotional (probably nostalgia caused) and there were parts I liked, but it's definitely not a 3 star.
I'll see the movie when it comes out on the 7th of March and I hope that my lack of enjoyment is due to a language barrier.
I don't read many novelisations so this might be typical of them, but this is a very direct adaptation of the movie. I wish it had added extra details and expanded upon plot elements, because it really doesn't take advantage of the change in medium. Instead it does its best to describe exactly the cinematic elements going on