I picked this up for 2.50 from a used graphic novel section at a local comic store (one of the two that I frequent).
It was a very cool book. The kind of thing I wish we could see done by American creators, but, alas, even at Vertigo, there's little interest in this kind of project. American comic creators and fans seem to be far too superhero-centric for a project like this to fly.
I'm not really sure how to describe it. Perhaps as having the ecological message and post apocalyptic sickness of Nausicaa of the Valley of the Wind mixed an aquatic setting and then laden with Gallic pessimism.
Highly recommended to put on your graphic novel shelf.