per jobs it sounds like the official policy towards unlocking/hacking is not in its favor, and in fact seems as though their stance is to proactively prevent it.
http://www.macworld.co.uk/ipod-itunes/news/index.cfm?newsid=19123
First off, I have a biased position- I use an unlocked phone. But I think there is a difference between DRM and phone locking. It IS illegal to circumvent DRM, and not so to unlock a phone.
I see this similarity- DRM is mandated by Music Publishers, and Locking is mandated (presumably) by ATT.
I still feel that Apple will close current holes that allow unlocking, but my gut feeling (wishful thinking) is that they will not ReLock in the process.
Dave