Unlocking a Phone is now Illegal in the US

As reported by Ars Technica: since 01/26/2013, it is illegal in the US to unlock a phone to use it on another cell operator than the one intended. This is a consequence of a ruling that considers that software is not sold but rather licensed and that unlocking a cell is in violation of the Digital Millenium Copyright Act ("DMCA").

This doesn't cover jailbreaking.