The editors at Crave Online recently attended a Divinity II: Ego Draconis press event, and have put together a set of impressions based on what they saw of the RPG sequel.
What really stood out to me was how detailed the game was. Property ownership is nothing new to action /RPG's, but while it's true you can own a castle in Oblivion there's not a whole lot that changes when you purchase it. In Divinity II owning property is major event in the game and permanently changes how the game is played.
When you take control of your own property, you also inherit followers. Each follower has a different duty like the runners who venture out into the game world for you and bring back ingredients and supplies. You have helpers for almost every aspect of the game and they really assist you. This alone is plenty of reason to buy the game.