[Erundil]

I am most certainly a Christian, and I love all of Prof. Tolkien's writings, not just those pertaining to Middle-Earth. But, I'm a sucker for good writing in general, so that doesn't really mean that much.
Since Lalaith has extracted two questions from this discussion, I'll attempt to answer both as fully as I can in my sophoric state.
1.) Can Christians read and love Tolkien with a good conscience? Absolutely! There stands in the book nothing that I can think of that is discordant with the faith of our Fathers. I think that some are labouring under a minor delusion. They think that as Christians, we aren't allowed to read, listen to, or watch anything if it isn't explicitly Christian. Nothing could be further from the truth. When God became incarnate in the Man Christ, He came to not only save the soul, but to save the entire man and indeed, the entire creation. We, as imitatores of Christ, are called to influence every area of society for the better, not just by what we say, but by what we do and how we live.
A mark of a true disciple of Christ is the ability of finding something worth saving in everything. He obviously did. Even if Tolkien was an avowed atheist who swore to never mention relgion ever (any atheists out there, I don't mean to offend. I was one once too.), I would still read and love his works, for they are filled with examples that anyone can follow. Now, obviously, if Tolkien hadn't been a devout Roman Catholic, he would have written very different literature. However, as it stands, the works of Tolkien show forth vitures that all people know, for they are part of our very make-up.
2.) Can/should direct Christian analogies and metaphors be extrapolated from the text? I don't think they should. Tolkien specifically denied writing an allegory of any kind. He left that to his fellow Inkling C.S. Lewis. However, are there things that can be taken as allegories or metaphors if one wants to? Of course, as there are in all great tales. I think the greatest measure of Tolkien's success lies in the fact that his works can have such an impact on all areas of life, if one takes to heart the virtues that it teaches. In the same way, if men followed half of the instructions of any of the great philosophers, the world would be a much better place. If we really thought about the things that the great writers of yesteryear, be they Tolstoy, Faulkner, Milton, Shakespeare, Homer, or any other, we could indeed change our lives and grow to be more like God.
We as Christians make a distinction between 'general' and 'special' revelation. General revelation is that which is granted to all men, be it through nature, conscience, or great writings. Special revelation is that which is granted to Christians through the indwelling of the Holy Spirit, the teachings of the Scriptures and the writings of the Fathers. A measure of the evangelium is granted to everyone; one need not go to a church, open a Bible, or hear a preacher to find it. It is given to all without distinction. It falls to each to notice it and act on it.
And now, I leave you, for I have written more than enough, and I am about ready to fall asleep at the keyboard. Good night, and keep asking questions.