When you buy something on eBay or Amazon, you pay the seller, he ships the product and upload a tracking number.
If you haven't received the item, you can call eBay or Amazon and, basically, what happens is that if they have a tracking number that shows that the item has been delivered, then it is ok, otherwise eBay or Amazon reverses the transaction and you get your money back.
Is that possible with bitcoin? What if I buy a boat online for 2 bitcoins and I never receive it? Is bitcoin able to solve this problem?

Thanks