I love the
Wicked series books for the fact that apparently they are "NOTHING LIKE THE PLAY!" to the point that it angers fans of the stage version. If you have time, read some of the one-star reviews for the first book (http://www.goodreads.com/book/show/37442.Wicked). It's hilarious how mad these people get. It's like they've been betrayed, tricked into reading this divergence from their beloved baby. Since the play is based on the book, shouldn't they be upset at the play for switching things up and muddling their grey matter?
If they continued on reading the series (which there's no way in hell they would) no doubt this continuation of Maguire's alternative Oz history would further incense them. It departs even farther from Baum's original work...unless Baum discusses homosexuality in one of his books which I haven't read yet. The tone is more realistic and contemplative. Everything's taken more seriously than your great gran's fancy-free Oz.
I'm also a fan of these books for the writing. Gregory Maguire can string words together pretty well! He's a solid tale-teller too, although pacing can be his achilles heel. Those contemplations bog things down a bit now and then.
This is definitely not for everyone (certainly not for a certain few!), but if you liked adventuring in the Land of Oz as a kid and long for more now that you're all growed up (and are fully equipped with an open mind), this just might be the escape you were looking for.