Storm World: Hurricanes, Politics, and the Battle Over Global Warming by journalist Chris Mooney doesn't explicitly call the book "important," but the book review editor of the Cleveland Plain Dealer added that adjective to the version published there with my consent. As a member of the National Book Critics Circle, I have sent e-mails to some of the nominators for our annual award that Storm World definitely deserves consideration.
A Contract with the Earth by former U.S. Speaker of the House Newt Gingrich and conservationist Terry L. Maple. I still think the book will make an important contribution to the debate on global warming, but I am disappointed so far in what it fails to say.
The Canon: A Whirligig Tour of the Beautiful Basics of Science. As a self-described "serious science reader," I found it a bit simplistic and "too clever by half" in its colorful prose, but I am sure it will have an enthusiastic audience of readers who want something lighter and more enticing than, let's say, Storm World.
The Cloudspotters Guide.
Physics : Decade by Decade by Alfred B. Bortz, Ph.D.. Clicking the link gets you to a description of the book as well as an academic colloquium that I am hoping to offer on the topic, as viewed through the lives of ten exemplary scientists.