I think the one about not having children was pretty funny. Two oh so wrong things with that.
1) In North American, population growth is in the negatives. We are experiencing population DECLINE. If it were not for immigration, we would probably be having some pretty big problems.
2) World population is now expected to level off at 11 Billion rather than the 20 Billion expected only a few years ago. We're going to reach the peak and start falling off.
Now all we need are some cleaner industry, hydrogen powered cars (in the works!), and some environmental consciousness and things will work out nicely.