A new type of ace is introduced, the "jumpers". The way this power works, and the way it's introduced into the Wild Cards world, seems contrived and in retrospect (I finished this book a few days ago and I've finished the next book, too) a desperate attempt to breathe some new life into parts of the story that really should have been finished already.
I like the multisodic, simultaneous timelines of the other books. But this book feels like it plods along like a donkey, not really caring where it's going or how long it takes to get there. If you're committed to finishing out the series, it's palatable, but PLEASE don't read this book as an introduction to the world of Wild Cards.