One of the first things I noticed about Zombies vs. Unicorns edited by Holly Black and Justine Larbalestier (Simon and Schuster Books for Young Readers - Margaret K. McElderry) is the cover. Mine has a jacket, but only about half a jacket. The zombie and unicorn cutouts are blurry and confusing because there's a bright pattern underneath. If you're me, the first thing you do with a hardcover is remove the jacket for safekeeping--which reveals a gory, hand-drawn scene something like what would happen if Where's Waldo walked into a nightmare. So, you see, you're in for a bit of subversion right from the get-go!
Team Zombie, led by Larbalestier, and Team Unicorn, led by Black, contribute a variety of stories about each, framing the zombies and unicorns as traditional and not so much. Some of the stories have a strong horror bent while others veer into romance, humor, fairy tales, and so on. Each is introduced with commentary from the editors, and while this could easily have come across as in-jokey and twee, it was pretty funny, particularly as the editors stuck to their good and bad cop roles. (Of interest: both gay and straight relationships were represented in the romances.)
Short story collections can be a tough sell, I think, but I also think that they're good choices for reluctant readers who don't have to commit to an entire book, and a good experience with an author's story can lead to interest in entire novels. The authors included in Zombies vs. Unicorns all write novel-length works as well. My favorite stories in the collection, in no particular order, were those by Libba Bray, Kathleen Duey, Meg Cabot, and Maureen Johnson. Given this subset, it's a tie between the horned ones and the undead.
I read this book as a first-round judge for the Cybils Awards, which means that I may have received a review copy from the publisher (or not; I own a lot of the books in this category). I read some books nominated for the YA fantasy and science fiction category in 2010 before the nomination period, and may have already reviewed them or declined to make a public review; these books might not have a Cybils post tag. As a first-round judge, I was tasked with helping create a shortlist of books. My personal reviews do not reflect any actions or discussions of the judging committee.