I read "The Hunger Games," and have sampled some other first chapters (bless you, iPhone Kindle app). It's a weird genre -- as hard as it is to watch kids in danger in movies, in books, you get a sense of their inner strength, and somehow you can almost forget they're supposed to be kids.
I would also put Kazuo Ishiguro's wonderful "Never Let Me Go" in this category, even though I suppose technically it's meant for adults, not YA.
I'm sure this trend, and those of wizard and vampire novels, will have moved on by the time Kelly is ready for YA list. Who knows what fad will have replaced it?