I wasn't sure how I felt about this series after Vol. 1, partly because sometimes it takes time to feel comfortable in complex fictional worlds, but mostly because I wasn't sure where this was going. After Vol. 2, however, even if I don't know specifics, I have a definite feel for this world and the things Carey and Gross are trying to say. That feeling is "awesome."
I can't really sum up the plot of this series very well without giving anything away, so I won't even try. Half the fun is experiencing the ride yourself. Seriously. Go out and buy Vols. 1-2 right now. It's the whole package: fun and intellectually engaging. The Unwritten is basically like the entire reason God invented post-modernism.