One of the reasons that Europe works so well for war games of any type is the fact that the Mediterranean exists. In a way, you can think of all of Europe is a giant peninsula, that borders all of the Mediterranean, a giant bay. Bays and peninsulas, especially large ones, offer the most 'fun' when it comes to armies and fleets. Islands help too. (Italy, Britain, Scandinavia, Turkey)
To create another popular world map based Diplomacy game, you'd need a balance of these things. The problem is, outside of Europe, it is very hard to find. South America is one big blob. Korea, Japan, and Asia could be fun, but again, Asia is blobby.
In fact, there is only one other area of the world I can think of that has what's needed, IMHO, to create a fun map. It is here:
http://maps.google.ca/maps?f=q&hl=en&geocode=&q=&ie=UTF8&ll=47.783635,-63.720703&spn=16.606422,28.256836&t=p&z=5
The East Coast of Canada could provide for much fun IMHO. I'm wondering if anyone else see's what I'm talking about, and if so, if they'd be willing to help me make a map
