Some key differences for you to consider:
1) Second Son is a launch window title, the Devision is likely fall 2014.
2) Second son has a lot more going on, from large scale destructable environments, crazy particle effects and aerial transversal which requires greater draw distances. All at a rock solid frame rate. Its unfair to compare it to a very grounded 3rd person FPS.
All the below is in-game by the way.










