Those images look nice. Has the guy written more books in the series since the first post?
There are four books in the series, all of which were published before Peter Jackson got the rights in 2009.
The first one, which is called Mortal Engines, is a self-contained story... but there is an open-ended aspect to it. Not at all a cliffhanger, and the story has a resolution, but Philip Reeve knew he planned on writing more so he built a world and a character relationship to that end.
I had no idea whether there was even an inkling of a thought of adapting the other Hungry City books, but given in the trailer they talk about this being a "new epic saga," there might be some intention of that if this movie does well.