Stanford professor Paul Ehrlich delivered a seminar to the Long Now Foundation a few weeks ago, and you can watch it here. Ehrlich offers an overview of the "state of the world" from the point of view of an ecologist/biologist.
Ehrlich is the co-author of The Dominant Animal: Human Evolution and the Environment.
Paul R. Ehrlich is a co-founder with Peter H. Raven of the field of co-evolution, and has pursued long-term studies of the structure, dynamics, and genetics of natural butterfly populations. He has also been a pioneer in alerting the public to the problems of overpopulation, and in raising issues of population, resources, and the environment as matters of public policy. Ehrlich is the author of The Population Bomb, and many other books, as well as hundreds of papers.