This one won't steal the magic system, however. I want to keep thinking about it more before I do that--I don't think I got that magic down very well in that book.
With this book, the part I'm stealing the role reversal of the two sisters. (They were cousins in Mythwalker, but this will work better.) The firebrand younger sister who gets sent off to be married to the emperor--sent instead of her older, more-refined sister because the king knows war against the emperor is inevitable, and can't bare to part with the sister who is supposed to go. The older sister, upon discovering this, runs off to attempt a rescue--but, of course, she has no experience with such things.
Fuzzy: A PANDORA rewrite is far, far off, I'm afraid. But, I haven't forgotten how much you (and a couple of others) are pulling for that book. Perhaps you should keep working on me!
Both MYTHWALKER and PANDORA, by the way, are available for anyone who wants electronic copies of them. Be warned, however, that MYTHWALKER was never finished, and PANDORA is rather rough. (I wrote it before ELANTRIS.)