Ah, an explanation of why superpowers appeared when they did! A combination sort of fantasy/superhero/SF sort of reason. I note that this reason was not only integral to the plot, it was the driving force behind it. The complications of world-building is that sometimes it has to drive the story.
Also liked the very realistic treatment of people's reactions. On one hand, the fear of the powers, on the other hand the freedom of the Actives. . . though no one pointed out that if they can control people who can throw around tanks and the like, what can they do to Normals?