Ok, so I never did this before as I have always picked up my new phone from Apple, but have a question when I get my new 4S tomorrow from Apple. Do I use the SIM card from my iPhone 4? or do I keep the new SIM card in the new 4S and Activate thru iTunes, or do I have to call AT&T? I figured it is as simple as using my 4 SIM card, but not sure if there are changes in the 4S SIM cards, does anyone know for sure???