From the interview:
Salvation or Ruin
This is a piece that nicely illustrates a major component of the game - environmental territorial control. As your nation expands and lands once barren are replenished with magic, you will see a dramatic shift in the feel of the terrain.
Kingdoms of Men will see their countryside turn lush and green. Animals return to lands healed and the surrounding ocean reflects the blue sky above.
Play as a Fallen Empire, however, and things just get nasty. The ground turns to ash, the forests lose all color, and the animals of the land twist into nightmarish creatures of death and disease.
I'm guessing most people will play as the Fallen.
You're likely wrong on that. In games where this option exists, the "good" side usually gets more popular. More people like nice terrain and things then like wastelands.