Recently checked the Advent Children site in the character section, and they have the names of all the characters in the movie. Although they might add more characters, I highly doubt it.

I bet that many of you have already seen this, but the reason for this topic is that maybe Cid will not be in the movie. Although it would add a great comic relief to the movie if Cid were in it, I think Square-Enix wanted to make FFVII:AC a completely serious movie.