Minor spoiler ahead!
After several years of anticipation, today I watched the first showing I could find of Final Fantasy: The Spirits Within and found myself greatly disappointed.
While the movie had many weaknesses, the main one is the characters' complete lack of depth and development. The sparse dialog between the one dimensional characters seemed very contrived and utilitarian -- just enough to provide necessary background information and keep the predictable plot rolling along, revealing little information about the characters. There were a few amusing one-liners, but for the most part the characters seemed very flat and dry, including the protaganist Aki.
Consequently, as many of the main characters were killed off I felt nothing for them, which sharply contrasts with the strong feeling of connection that develops in many of the Final Fantasy games. I often found myself asking "Who are these people and why should I care that they've died?"
Sadly, the movie didn't really provide me with an answer.
As a Final Fantasy fanboy, there are also a couple of omissions that I can't really hold against the movie, but have still left me feeling a bit unfulfilled. The abscence of swords seemed strange to me, as even in the more sci-fi oriented settings of Final Fantasy 7 and 8 swords found a place. Somehow it just didn't feel like Final Fantasy without a protagonist who weilds a ridiculously oversized sword, and I was a bit let down (Freud might have something to say about that, heh). Second, where is the amazing music of Nobuo Uematsu? It seems very unfaithful to the series to let someone else create the musical score, especially considering the beauty of some of Nobuo Uematsu's orchestral works.
I think the fundamental problem with the Final Fantasy movie is it fails to be immersive in the way the games are, which I feel is a problem inherent in the nature of its medium. I just wasn't absorbed into the world of the movie.
With no sense of interaction with the characters and 2 hours rather than 50 hours of gameplay in which to develop the personalities of the characters, Square's epic tale just can't quite unfold.