You can add unlimited URLs as a Premium Member. You can also target all the URLs you enter by country. The weight feature only comes in to play when you have more than one URL targeted to the same country. Then you can use the weight feature to set one site's weight higher than another to get that site more traffic. As a Premium Member, you must have at least one site targeted to World as a catch all URL, so when there are no surfers in the countries you are targeting, it will use the World Targeted URL.