AT&T has posted a video of the procedures whereby a current AT&T and iPhone 2G customer can "hand down" their original iPhone and upgrade to a new iPhone 3G. One procedure involves a SIM card swap, and the old iPhone can be reactivated when the customer is ready.

"The big question customers have been asking is, according to the video, "can I give my old iPhone 2G to someone else as a 'hand-me-down'?" The answer is "yes."

In one option, according to the video, the old SIM is moved from the old phone into the new iPhone 3G and the customer keeps the same phone number. The old iPhone will need a new SIM card which AT&T can supply, and then the iPhone 2G may be (re)activated in the store on, say, a family plan, or the customer can take it home and activate it on the AT&T network as a new phone as before. "When you (re) activate your original iPhone (2G) is up to you," the spokesperson said.

In a second option, explained to iPO by an AT&T spokesperson, the customer need not bring the old iPhone into the store. An upgrade can be conducted with a new iPhone 3G while still keeping the same phone number. What the customer does with the old iPhone is up to them.

Although AT&T didn't specifically mention it, this presumably includes someone you may elect to sell the old iPhone to.

AT&T has also published a checklist on things the customer needs to do to be "iReady" for the new iPhone.