To put aside War and Exploration, no one has said anything about commerce yet.
I think commerce would be very different in each servers, due to servers having different sizes.
"Now, every server has a different map and they are procedurally generated. This means they wont all be the exact same size, and they wont have the same ratio of land to water. So some maps may take even longer to cross, while others may be quicker."
^mainly revolved phrase in this reply^
The flow of commerce can be different from each server, money can flow differently from location to locations (depending on distance away). Well, depending on where you're going for some money, location will differ. Either it will take 1 in real-life hour to get from A to B to get some good profit, or 10 hours in real-life w/ some OPC assistance to get some mad profit. Or, if you're just a CASUAL, you'll just dedicate 20 minutes of your time getting some money.
Apart from that, I'm really excited on how this world is gonna shape, and how each server is gonna be shaped like.