I seem to always have a problem with shipping to the wrong address. Twice this week I've had to go back and change the shipping address. I noticed that there's a big box on the confirmation page to remind people to check the address, which makes me think that I'm not the only one who has done this. I think I figured out what the problem is though, and how to solve it: on the page where you select an address, just don't pre-select an address. Make people select an address instead. It might be slightly less convenient for people who always order to the same place, but it would be quite a bit more helpful to people like me who assume that the default is where we want to go. In any case, it's just a suggestion of a place that a small change can make a big difference.