Follow the instruction strictly, and you don't have to wait for 6 months! I bought the phone on Thur, submit the request to unlock on Friday, and get the code on the following Monday! The phone was with AT&T service for a total of ZERO day!
The key thing is DO NOT power on the phone until you get the code (or at least do not power on with the AT&T SIM card provided - some success cases reported), and chose "Non AT&T Mobility Customer" when requesting for unlock code.
So, one can still get it work internationally "out of box" - all he/she needs is the IMEI code which is available from packing material/box, submit the IMEI to AT&T website for unlock code. Unlock code should be available (through email) by the time he/she receive the physical phone outside of US, he/she just need to replace the SIM, power it on and key in the unlock code and start using it with the telco's service. I've gone through the process personally!