Now, I'm not familiar with the series but the collected wisdom of the Internet informs me that the Mortal Engines books are best described as "post-apocalyptic steampunk." After the world as we knew it was blown to bits by nuclear holocaust and geological instability, cities took to the air. From what I understand, these "Traction Cities" barter resources and war with one another in a Mad Max-style scrabble. The only Traciton City recognizable to our innocent eyes is London, the rest are mashed up of whatever land masses / airships survive.
A spokesman for Jackson refused to comment, though no one associated with Wingnut or WETA denied that the film was in the works. WETA is said to be working on designs as you read this. It would be a long time coming unless Jackson hands it off to another director and acts as producer which could very well happen. So, I'll turn this over to Mortal Engine fans -- is this a series that would actually be possible to adapt? Is Jackson the man for the job, or would you prefer seeing someone else take the helm of the Traction Cities?