In a blog post, AT&T clarified its policy on unlocking devices, saying it will release your phone as long as you have fulfilled the terms of your contract and as long as they have the unlock code. How generous: you are free to wander the wild world of carriers once your contract is up.
The post explains that normal people have never really had anything to worry about with phone unlocking. If you have a contract, you have to finish it or pay to get out of it, but if you do that you're free to go. The company claims its position is totally consistent with the White House's statement earlier this week.