I started reading World After right after finishing Angelfall. The pacing of this book is different from the first one. In a way, it reminds me of Lord of the Rings. There the first book was mostly about the journey and finding out about the world. In the second, you find out more, and the building blocks of defeating the foe emerges. So the third would be the big battles. We'll see.
There isn't an easily progressing story in this one as in the previous book. It may be the reason that people feel the pacing is different, but now that I think about it, not so much. A lot of things do happen, but Penryn mostly just floats from happening to happening. It feels a bit forced, and too incidental. Of course, if I think about it, and take into account what Paige's goal was all along, things make more sense. The random events feel no longer so random, except for a few.
The characters stay mostly the same. The whole thing is just about two or three days, so no wonder. There are some side characters introduced that will probably play a part later, but they are just moments now. Maybe the doctor feels more rounded, and of course Clara. The main focus of this tale is the information though.
Overall, an enjoyable sequel. Still not seeking out fanfiction, but will read the third book once it comes out. I just wasn't blown away.