The Mortal Engines by Philip Reeve
Its been out in England for several years, but Scholastic just released the whole four volume Predator Cities Quartet at the end of May. This first book is spiffing adventure in the vein of Flash Gordon serials or the original Star Wars films. Its a post apocalyptic/steampunk romp through the ruined remains of Europe. The cities that remain are all on wheels, moving around the continent looking for smaller cities to devour in what they like to call Municipal Darwinism. After Londons greatest historian hero brings back something awful and mysterious from the War, Apprentice Historian third class Tom Natsworthy and his companion Hester Shaw traverse Europe trying to get back to London and figure out what is going on. Ages 10+
--Reviewed by Steven from Books Inc. Palo Alto!