Currently, only the resources are random. Everything else is fixed (shape of the continent, position of landscape (woods, mountains), starting locations (you don't always start at the same location but the locations themselves seem fixed)).
Note that there are a couple of maps, so you won't get the same map *always*. But as I said, it only took me four tries to get a repetition.
Also, not only the mountain ranges or forests should be random but also the shape of the map. As it stands, after a while I will always know that, e.g., "to the east, there are two more empires and if I rush to the west, I can occupy a strategic choking point."
Neil: I appreciate the fact that user created maps can be imported easily, but let's face it: Many of those maps will be bad or built in order to have an interesting effect or situation. Only a few will be simple standard maps. So I'd rather have random maps, thank you. Plus, I assume we will be able to look at the maps before downloading it, which kind of defeats the purpose of having an unknown map.