Read this book recently. Highly enjoyable and easy to read, save a couple chapters here and there I skimmed. I also read his new book called Collapse, which I felt had some good lessons for why societies fail and how we industrialized societies are on a similar path to destruction through overexploitation of global resources. He analyzes both ancient and modern societies to explain how things worked or didnt work.

also, check out PBS, which is currently airing a documentary version of Guns, Germs, and Steel!!!

http://www.pbs.org/gunsgermssteel/