Cartograph is a mapping program for Minecraft that allows you to view your entire world in various ways, including a cubic mode, a google maps-esque view or even a (if you like it) dirt view. This program seems to show the texture packs that you used in your world and not just show the default texture pack (if someone finds out otherwise, post a comment!) and you can choose to view your world in either a nighttime view with illumination effects from lava and torches, or you can view it in the regular daytime manner which will show full color and essentially the regular look of your world. This program would be ideal for showing off your metropolis-like city without having to take a scrapbook full of screenshots. I'm also assuming that this program isn't Mac compatible seeing as there is no link or reference to an OS X version, so I will also link an OS X map viewer shortly.
Notes: Large maps may suck up a lot of CPU when being processed by this program, so if you've got a continent-sized map, don't try this on your 1998 Compaq laptop.