If you wait to play until you built the whole world,  you will never play.  Its ok to come up with a piece of the puzzle and build it one peice at a time.  Will it be perfect?  No. But at least you get to play in the here and now!

Really good points, Carpenter!  Especially about the way that communication and transportation make the world "smaller" than it used to be.  In fact, with the internet, cell phones, etc. the world is even tinier than it was 20 years ago when I started my current campaign.

I was just watching a baseball special about the '89 earthquake that interrupted the World Series that year (both teams in the Bay Area).  At the time, the ENTIRE WORLD had to rely on Al Michaels (who was broadcasting for ABC at the time, I think) for things like news, updates, road conditions, and lots more.  He pointed out how nowadays there wouldn't be thousands of people "in the dark" about what was going on.  Not only would every news station give you every possible angle, but every civilian present would have all the latest news on their cell phones and be able to broadcast pictures of what was happening all around the world!  It's such a different world we live in now, so things like communication play a big part of a campaign world.

Transportation - regardless of era - can be problematic for hero groups too.  If you have one of the heroes who can instantly teleport everyone to the moon and back (or anywhere on the planet), it can change the scope and magnitude of adventures and how the GM can make thrilling stories that challenge the protagonists.

Well put, Mike.  I agree that it's nice to have a flexible group that allows you to sort of build things as you go along (for the most part).  As he said, that's assuming that no major events occurred that deviate from our own known history.

In our universe, we've explored the characters' pasts and the history of our campaign world as we've gone along.  The events that happen in our world (like September 11th) happen in our campaign world, and it's rare that something in the campaign world contradicts what we all know and read in the daily news.

One significant event for us (that I introduced probably 15 years ago) was that a group of paranormals attempted to form their own sovereign state (I was heavily influenced by the latter issues of the Elementals with that).  They ended up taking over the African island of Madagascar, and since that time in our history it has been run by supers.  It is now known as New Babylon, and it is mostly made up of a number of city-states.