Well, if you want to know how I did the buildings in the original, it's not terribly exciting. I just drew them in with a brush!
But I do have a nifty trick to show off that's a heck of a lot easier. But that's still... Oh, at least three or four weeks away. Next week will be coloring. After that, adding the water will take at least an episode, but more likely two (but it's a darn cool technique that you can use for a LOT of things). Then the roads and buildings will be one or two episodes. Then two or three episodes of finishing touches.
Whew! That's got my next couple of months worth of podcasts covered before I start on another map.