I think I was right in my review of the first of this series, Tomorrow When the War Began. I felt that one was good, but missing something.
This one, book 2, is much better. Much more action and much more character development helps to fill in the gaps from the first.

It's feeling much more like Red Dawn.

Marsden really has skill in writing in the voice of a teenaged girl. I'm impressed.

I have a feeling that I will devour the rest of the series pretty quickly.