Recent Game Informer mag has a great thing on AC3, outlining all the details about little stuff we hadn't seen mentioned before, like outlining how the clubs, brotherhood and trading works.
The trading system sounds awesome, you don't buy stores anymore but rather pour resources and crafts into your Homestead, and then you send out your wares via trade routes. Clearing out forts in the frontier can give you access to better trade routes and thus more money. Similarly, because your trade cart is a physical thing moving through the game world, it can get attacked at any time, meaning if you don't want to lose profit, you either have to send your brotherhood out to defend it or go defend it yourself. Also, you can attack OTHER trade carts and steal their goods. AND buying products that you supply at a store gives you a discount on that product :P
So many cool things like that. For instance, in the Homestead, not only do all your allies and adventures bring more people to your land (Which increases productivity) but mementos and trophies from your adventures gradually adorn your property. And you have a secret trapdoor in your house that opens up Connor's hidden basement, where all his Assassins clothes/Weapons are kept.
