I read about this book on John Scalzi's blog. It's apparently filled with art plates, and the few I got a glance at from that blog were very nice.

It's apparently a retelling of WWI with some cool sci-fantasy mixing it up. The Central Powers are indeed a steam-punk inspired, whereas the allies are influenced by organic technology. The title of the book refers to a living airship called "The Leviathan", fittingly enough. There's a couple sci-fi tropes mixed up in a rather cool and unexpected way, IMO. It's definitely on my reading list.