Japanese website Dengeki Online, recently interviewed composer Nobuo Uematsu. In the interview Uematsu talked about Final Fantasy Advent Children, amongst other projects.
He revealed that three different styles of music will be used for the movie; rock, classical and folk. He also said that while he is not intending to re-use the music from the Final Fantasy VII soundtrack, he was considering using it on a few occasions. In particular he is thinking of using three of the most popular themes. Those being the main theme, Aerith's theme and One Winged Angel. He said that at the moment he is trying to decide which of these songs should be used and during which part of the movie.
Also when speaking about the upcoming Final Fantasy music tour in Japan, he mentioned a possibility that a new unreleased composition from Advent Children or Final Fantasy XII may be performed.
One more interesting part came out of the interview. Uematsu mentions a "yet-to-be announced" project. This has also been mentioned by Tetsunya Nomura in the past. Fans of Uematsu's music will realize that all of his major work has been on the Final Fantasy series, with some minor work for a few other games. Of course we are only speculating here, but what if the un-announced project is in fact Final Fantasy VII-2. It would make sense, seeing that Uematsu is the main composer for Final Fantasy and has not had a major role in other titles. Plus, if Final Fantasy VII-2 is in the works, then it would not be announced until after Advent Children.
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