You may remember that last year, the DMCA exemption on unlocking phones was smacked down. Well it's going into effect this Saturday. So starting tomorrow, unlocking your phone will be officially illegal. Yay.
Unlocking phones without the express consent of the carrier who locked them became illegal thanks to edits to DMCA exemptions back in October, but it's only now that the 90-day grace period is running out. Locked phones purchased in the 90 days after the ruling are still game to be unlocked, but from here on out, for an unlocked phone to be legitimate, it'll have to have been bought that way or come with a permission slip from your carrier.
It's not the first time retracted DMCA exemptions have threatened to mess with your ability to mess with your phone. Jailbreaking and rooting almost became illegal again because of DMCA exemption changes. Fortunately, the same batch of modifications that illegalized unlocking will also protect phone jailbreaking for another three years. But it's still not allowed on tablets. Not than anyone is likely notice that particular indiscretion.
These changes won't, of course, limit you ability to unlock phones anyway, but it will give carriers a bit of a heavier stick to wave at you if they catch you using an unlocked phone they didn't authorize; they can tell. There are also a few technical loopholes. Legacy phones, i.e. "used (or perhaps unused) phones previously purchased or otherwise acquired by a consumer" are still cool to unlock, and that definition has a little bit of play in it. But the practice of unlocking your carrier-discounted phone is still going to be a crime, so get ready to deal with this brave new world, or live the life of an outlaw.