I second the Dennett recommendation. Along the similar lines, on my wish list for planned future reading are Robert M. Hazen's _Gen-e-sis: The Scientific Quest for Life's Origins_, Chris Turney's _Bones, Rocks, and Stars: The Science of When Things Happened_, Carl Zimmer's _Evolution: The Triumph of an Idea_, and Sean B. Carroll's _Endless Forms Most Beautiful: The New Science of Evo-Devo and the Making of the Animal Kingdom_.