It's a tricky one, the maps *are* procedural but at present they're restricted to a very small and now fully mapped possibility space, I assume to avoid unpredictable worldgen edge cases during development. They may expand on this after all biomes and game mechanics are locked down.

And if they don't, as I say worldgen can be modifed by the community. If the terrain starts getting boring people will absolutely add their ideas to the stew.