Between the rise of third party vendors and the recent change in DMCA policy, the need for iPhone software unlocks is steadily dwindling. But that doesn't mean that the method is obsolete, as there are still many people out there with older iPhones.
And if you happen to be one of those people, you'll be happy to know that MuscleNerd has confirmed that Ultrasn0w was quietly updated this week to support iOS 6.1. So if you're on an eligible device and baseband, you can unlock on the new firmware...