In my scenario, it isn't a big problem since we're using shipping by quantity ordered... however.....

The issue is still there when you first go to the cart checkout, you are asked to calculate shipping before you can continue. That is fine.

However, on the NEXT screen, you can change the shipping information, and it doesn't re-calculate shipping. This is not good, since someone could use a local address to calculate shipping for the cart, then have something shipped to Timbuktu on the next screen without re-calculating the shipping.

Multiple ship-to addresses should really be chosen from the first cart screen, so that the shipping calculation is correct; and if a different shipping address is chosen (on that first screen) it re-sets the shipping method, so they have to choose it again if they've changed the address.

Make sense?