Hope u guys can help me out.. 1) If I preorder my iphone 4 from Apple.com and have it shipped to my home.. Do I still have to go to the AT&T store to activate the phone? Or it going to be done already by the time it shipped to my home? 2) Will the Sim card be a different one than iPhone 3G? If so.. how can I transfer my contacts into iPhone 4? 3) Will the OS3 APPs work on OS4? Thanks!