Hmm yeah... Fantasy in the Sky has always been set to music. However, fairly new (last year or two) is Wishes, which is a completely different fireworks show, complete with music from the people who created Reflections of Earth. I haven't seen it, but I'm being careful to not hear much about it so that I'm completely amazed when we go in June 05.
Anyway, is this what you were thinking of?
Jack