
A War of Gifts takes place in the universe of Ender Wiggin, so if you haven't read Ender's Game, you won't know what's going on, because there's not enough context given to appreciate or undersatnd most of the supporting characters. But for those who have, it's a meaningful addition to the characters and environment of the Battle School.
The main character is a Battle School Recruit we've never heard of--Zeck, the pacifist son of a fundamentalist Puritan preacher. I don't want to give anything away about the story, except to say that the book is a fantastic little story about tolerance, religious piety -vs- "blind obedience," and the spirit of giving that is such a trademark to the Christmas tradition (regardless of your religion or set of beliefs).
The themes can be a little heavy compared to most Christmas stories. But it's certainly an interesting read that discusses good, uplifting issues of human experience and relationships which transcend cultural and religous boundaries (although there are some subtle references to Christian themes if you want to find them there). So if you're looking for something positive, but just a little different this Christmas, or if you're a fan of Ender or Card in general, check it out.