I'm sort of suspecting that people who are drawing parallels between the Christian messages in Tolkien and Lewis haven't reread the Narnia books since they were little kids. While the blatant Christian message is not something you notice when you're small and reading a book about the adventures of some children and some talking animals, it really beat me over the head pretty hard as an adult rereading the same books. Tolkien is far more subtle and as somebody else pointed out, he does take a lot of elements of his stories from Celtic folktales that have been around since waaay before Christ. Lewis on the other hand is very much aware that the bulk of his audience is children, so he lays it on pretty thick.
While I can understand making a movie that appeals a lot more strongly to people of one given faith - people who don't want to listen to Christian messages can just avoid the movie (and we've seen that if a movie is seen as a good Christian film it can and will make a mint and a half, and that one was seen as too violent for children!) - I think that it's a lot harder to finesse this kind of thing in a theme park that is supposed to be (although it sometimes seems unrealistic at this point) a global tourist destination.
I guess, though, that before we make any judgments on the viability of such a scenario, we'll have to see what Disney does with the books. If they somehow manage to quiet down the Christian allegories then maybe this would be a good ride/land. Otherwise, I think it's just begging for controversy. I mean, I know there will be people who will say that Christianity is the majority religion in America just like English is the majority language so of COURSE it's fine and I'm an un-American PC nutjob for even suggesting otherwise - but hey, that's what I do. Disney is trying to make money here and I think that alienating many subsets of the incredibly diverse LA metropolitan area would be a bad thing.
That said, thanks to this thread, I'm watching the Apple trailers featurettes on the movie - and it looks freaking great. So, I think my official stance is going to be to wait and see. I'd entrust WETA with my own dreams.
Of course, the question of whether we want more pre-established characters and stories at DL is a whole other issue...but sometimes that too seems like it's moving towards moot.