Any villages within a snow oriented biome should be composed, primarily, of wood. Permafrost would make it very difficult to mine stone and other more durable resources...so it's more likely that you would come across log cabins and a cattle pen with a few wolves kept as hunting dogs.In fact, it would make sense to switch out the Iorn Golems for Wolves in these villages...again, iron would be difficult to mine due to the frozen terrain.
In the more extreme ice biomes...igloos are much more likely.
Really, they could go all out with biome themed villages and I would love to see a huge update on them.
Also, villages are meant to be rare. One spawning per biome area would be really overpowered, as the player would not have to look very far for iron, diamonds, tools, armor, rare horse armor and saddles, and even obsidian. I'd like to see them in different biomes, just not 1 per biome that spawns.
I don't think they meant one per biome area, I think they meant one type for each biome (AKA a jungle village, a swamp village), though I wouldn't support that anyhow.
It would be nice to have villages specific to the biome (AKA igloos for ice plains, perhaps different types of houses for different biomes, docks for villages on rivers, etc.), though if igloos are implemented, they had better be made of packed ice or else torches would be a disaster. Also, the igloos would need doors, since the villagers will not recognize a house without a door (it's part of the code), and would wander around until they died. But doors would look rather weird...