Straight from the horse's mouth at the bottom of the page: http://store.apple.com/us/browse/home/shop_iphone/family/iphone?mco=MTE2OTU
"For non-qualified customers, including existing AT&T customers who want to upgrade from another phone or replace an iPhone 3G, the price with a new two-year agreement is $499 (8GB), $599 (16GB), or $699 (32GB).
"For non-qualified customers, including existing AT&T customers who want to upgrade from another phone or replace an iPhone 3G, the price with a new two-year agreement is $499 (8GB), $599 (16GB), or $699 (32GB).