Developers answered a few quests regarding multicore support in their reddit AMA: https://www.reddit.com/r/IAmA/comments/2x4mf9/we_are_colossal_order_the_team_behind_cities/?sort=confidence
To the point: https://www.reddit.com/r/IAmA/comments/2x4mf9/we_are_colossal_order_the_team_behind_cities/cowups4