Got the new 4 today. I used my daughters upgrade to get it and giving her the 3GS. I called every AT&T store today asking for a micro sim. No one would give me one. They all said they had to wait until tomorrow since that was launch day. So I took matters into my own hands. I took my old sim out and cut it down to micro-sim size. I just used a sharp pair of scissors. I dropped the cut down sim into the 4 and plugged it into iTunes. It activated fine and its running perfectly. I called AT&T and told them what I did and they reset my daughters line and I'm done. Too easy and now I don't have to fight lines at AT&T tomorrow.