-Every town has it's own Economic System. If you destroy a city's means of income, they'll need to buy from another nearby city, and prices in the city will go up or some products will not be available in that city at all.
Flat out, thats pretty awesome. The idea that I can affect a cities economy, is awe inspiring. Maybe, if you kept selling animal pelts in a particular town, the price of those could go down because they have an excess of them. The two things that have gotten me excited are:
A trader character becomes extremely viable now that we can buy things in a city where they are cheaper then go to a city with a lack of the resource and sell it for a very decent profit margin. If a character wanted to even be a dirty merchant, he could cripple a cities supply of say food, then bring it into the city and make a good profit.
My thief character could actually strip a city of it's wealth and destroy its economy. Thats what got me really excited, I could cripple one specific city and be safe in all the other ones.
Maybe I'm drawing too many conclusions from one statement, but this has a great number of possibilities. Some parts of Skyrim have me worried, but this is definitely not one of them.