Watching the trailer, It seems that not only is the Carthage we see visibly affected by the lengthy siege, but it's also changed in other ways. Take the most recent screenshot in the Stickied thread. In the trailer, there are a bunch of Carthaginian ships sunk in the harbour, which is awesome, and in the picture they're actively moving around the cleaner and un-destructed port. The screenshot therefore is either from an earlier stage of the 146BCE siege, or is of what the city would look like in the campaign. If this makes it to the release as an actual feature, this has got to be one of the coolest little things to be included thus far.