I saw a good TED talk on how third world countries are currently matching industrial countries in lifespan and number of children. We still have a ways to go to get all countries on an equal footing, but in some ways we are doing better than we would think.
I do share some of Ygirl's concern on the solution of some of the problems. Sometimes we make things worse when we try to make them better. Like organic farming is an example of that. It uses a lot more land for the same food yield and it is no healthier than what was produced in the first place. It just makes food more expensive and it causes more land to be developed.