I was just wondering if X had any religious symbolism? That Karen Kasumi (w/ the fire/inferno powers) character seemed to have some, but not much, biblical references and implications.

In a way it does have religous implications, the Dragons of Earth are the angels of destruction, and they want to return the earth to it's natural habitat before the human race started messed with it by constructing buildings, throwing alot of waste, causing pollution, etc.. The X series as a story itself does have alot of sybolism about the end of the world, and in a way, it goes hand in hand with religion.

I myself think that X is just an unknown number- stands for the unknown day in 1999, the day which is set to be the end of the world