This is kind of a long story and anyone from ATT or Apple who can help, please read. Received an iPhone 4 16GB today from Fedex. As you could imagine I was quite excited. i ordered the phone under my wife's account and planned to swap it to mine. This is where the trouble starts. I didn't plug the phone into itunes. First I called ATT to see what they could do to swap the lines. They weren't sure what to do. Called Apple and they tried to help but said ATT had to do it. Called ATT back and they tried assigning the IMEI and SIM to my account but it still wanted to activate on my wife's line since the SIM was pre-programmed for her number. This didn't work, but they did manage to kill my SIM in my 3GS. ATT said I need to go into an ATT store that has some micro-sims. Finally found a store that has them. Went in and they started the process. Here is what they did: 1. Activated iphone 4 under my wife's account. (burned that micro-sim) 2. Got a new micro-sim to setup under my account. Then it got weird. Apparently the micro-sims they have are for iPad's only and won't work correctly in the iPhone. They did actually activate it using the iPad micro-sim but then they wouldn't let me keep it that way. So after all that I have an iphone 4 without a SIM and we both are using our 3GS iPhones. I'm not sure I buy the "iPad only" micro-sim story but they said it was from higher up and there was nothing they could do. The ATT store people were really great and were excited to get the iPhone 4 working but couldn't. So to everyone who is doing an Upgrade Swap, beware. I'm not sure what the whole truth is but as of now ATT won't activate my iPhone 4 because they don't have any iPhone 4 micro-sims. Update: After going through all this I decided to cut my 3GS sim into a mciro-sim and plugged it into my iPhone 4. Since it had gone through an activation on the other line it now works with my cut SIM. I'm not sure for how long or how well but I can make calls and it shows the correct info. There still has to be an easier, legitimate way for ATT to do this.