AT&T has announced that the upgrade prices for iPhone 3G S will be $399 (16GB) or $499 (32GB) for customers who are still under contract after purchasing the prior-generation iPhone 3G, a $200 premium over the “standard” iPhone 3G S prices of $199 and $299. Using a pricing configurator found on Apple’s BuyiPhone.Apple.com web site, users can find out their individual upgrade prices based on the remaining length of their AT&T…
