Being the most diverse borough in the world, it's good to have a very basic understanding of current world events. If you're American like me, here are some very basic things to talk about when your kids play with their kids on the slide:
China: The Olympics are going on right now. Opening ceremonies were unbelievable. If you get a chance watch them online. Amazing in every way.
Russia/Georgia: Georgia is trying to compete with Russian in providing oil to the West. Russia doesn't like that and it's gotten messy.
South America: Hugo Chavez wants to be Fidel Castro but doesn't have the popular support. Chavez charging US oil companies more and more everyday for access to Venezulean oil - some have bailed altogether.
Yes the above might sound too basic, but it's a good way to start a conversation. Just set them up and let them speak.
And after reading the above, I now realize why I have very few friends.