14 DAY TRIAL // Apple has issued documentation detailing the steps you need to take (as an original iPhone owner) to move all your existing information to the new device. From buying the iPhone 3G to syncing all your old text messages, contacts and so on, everything is explained thoroughly, so you don't lose anything you previously stored on your first-gen device.
"This article explains how to replace an original iPhone with an iPhone 3G using the same carrier," says Apple on its Support page. "If you follow these steps to backup your original iPhone first, and then restore the backup to your iPhone 3G, your saved SMS messages, email accounts, photos, notes, and other personal settings will be present on your iPhone 3G."
US customers don't need their original SIM cards to make the move, since their original "account information will be transferred to iPhone 3G's included SIM when you purchase iPhone 3G." However, Apple notes that, "in other countries where the original iPhone was sold, you can use your original iPhone's SIM with iPhone 3G." Users are also advised to contact their carrier for additional information.
Users will need to make sure they have the latest version of iTunes and iPhone OS once they decide to start using iPhone 3G. That particular iTunes version will be iTunes 7.7, expected to launch before the release of the new device on July 11th.
Practically, you will simply need to repeat the process you used when backing up the information on your original iPhone (using the same computer) only you will need to confirm when iTunes asks you if you want to restore from a backup or set up iPhone 3G as a new phone. Naturally, you will have to select "restore", if you want your old information transferred to the new device. As such, you will need to select the backup of your original iPhone2 when prompted.
"After iTunes finishes restoring the backup you selected to iPhone 3G, iPhone 3G will restart. When iPhone 3G appears again in the iTunes window, select it," says Apple. As soon as this happens, start clicking the tabs to verify or change the items you want to sync. Click Apply to sync iPhone 3G with iTunes. That's pretty much it!
Still, your job won't be done until you properly erase all existing data on your old iPhone, should you want to sell it or give it to someone else (remember the Refurb iPhone memory incident?). Apple is now offering an option to securely erase your original iPhone so someone else can use it. This is done by tapping "Setting > General > Reset > Erase all contents and settings on your original iPhone."
The full document is available HERE. It's best if you have it printed or brought up on your computer screen when you decide to replace your original iPhone with an iPhone 3G.