A quick note on magic: I recently came across a site that had listed us in the following derrogatory manner: "The people at The Christian Guide to Fantasy acknowledge that: The Bible is real, despite the magic. Fantasy novels are not real, because of the magic. Christian fantasy is not real, but good, because the magic is for Jesus." I had to chuckle at the absurd presumption. But since it is a matter of some concern, I'll address it here.
What is magic in fantasy books? There are three main means of presenting magic in Fantasy: good magic, evil magic, and neutral magic. Examples of the first usually follow the hedges of magic that Steven Greydanus has outlined. Although good magic may not be overtly attributed to God, generally its practitioners are saintly (elves, fairies, aging wizards, stars, etc.). Evil magic is almost always represented as something demonic in origin. Neutral magic is that inherent magic to an object, person, animal, etc. A unicorn's horn is morally neutral magical in the same way that a fish's ability to exist underwater is morally neutral. Unsurprisingly, the majority of magic found in fantasy books falls into this third category - a fact that should not be overlooked.
(In some senses, one might say that a morally neutral magic is essentially good since God creates all things to be good and then man uses those things either in a moral or immoral fashion. This is true. However, for the sake of practicality, it is simpler to point out that until a thing is used it is essentially neutral in regard to human free will.)
The use of magic becomes questionable when it treads from the realm of fantasy - the clearly impossible - into the realm of reality - tarot cards, divination, etc. A fantasy story about someone who can cross their eyes and turn people into cats is generally morally neutral magic (the morality of his actions may be something else entirely). A fantasy story about young girls engaging in casting neo-pagan spells is more potentially dangerous.
It is important to understand the difference between the various uses of magic in fantasy novels. Most books remain in the realm of the impossible. Thus, for the Christian, there is no difficulty in reading and enjoying such novels. This is not because the magic is "Jesus magic" or "Bible magic" or "bubblegum magic" but because the magic is a fantasy device used in an impossible world in an impossible manner that has little or no bearing on our own world.
Hence, difficulties with fantasy novels isn't the use of magic, but rather the morals presented.
Is magic necessary in fantasy books? No. Magic does not a fantasy make. Theoretically speaking, the difference between fantasty and science fiction (and mainstream) is a question of epistemologies. Practically speaking, fantasy takes place primarily in another world, science fiction takes place in this world, and alternate reality takes place in this world with impossible or implausible changes. Magic, then, is merely a device for setting a fantasy world apart from our world; it is not the fundamental necessity.
Why doesn't the CGF review more science fiction or alternative reality? Why doesn't the CGF review supernatural fiction or horror? Simply: we like fantasy better. However, the reason why we don't review supernatural fiction (e.g., This Present Darkness or Father Elijah) is because supernatural fiction is its own significant genre, only loosely under the aegis of Fantastic Fiction. Ditto horror. If anything, one might link them to alternate reality meets "mainstream." Since, again, this is the Christian Guide to Fantasy, webspace, free time and interest are limited, we will continue to focus primarily on the genre of fantasy and not on other related genres. Those who would like a review site of those genres are more than welcome to create their own websites and share links with us!