I may be wrong, so don't accept this w/o checking, but I seem to remember a quote by the director of "Narnia" that made him sound almost hostile to the Christian underpinnings to the story.
But from what I've heard (I haven't read the books), Narnia is like Lord of the Rings in that an adaptation that is at all faithful can't help but have Christian themes.
You are right, the quote I heard was from the director. I read the books a long time ago, but as I recall, the two main Christian parallels are where one child agrees to betray the rightful king, Aslan to the evil snow queen. Then there is the a very specific scene where the children are hiding as they watch the evil queen and her minions attack and kill Aslan, and he lets them. THe children don't understand how such a powerful creature like Aslan doesn't fight back. Then he late ends up rising from the dead.
As I said, I haven't read this book for nearly 15 years, so my recall is a little sketchy.
I've read the books LOTS of times. If hollywood tries to remove christianity from Chronicles of Narnia, there wouldn't be any story left. They're obviously marketing to christians, especially if you look at the lineup for the soundtrack. I can't wait to see the movie.