This comes from iOS expert pod2g. He was able to get his iPhone 4 to run iOS 5.1 untethered, according to a recent tweet.
The bad news is that there doesn’t seem to be a set date for a release, so we may be waiting a while.
Below is the tweet he sent out:
Heya! My iPhone 4 running iOS 5.1 is now untethered 🙂
For now, you will have to run tethered if you want to use iOS 5.1 jailbreaks. This is a huge pain if you have an iPhone, because you have to be able to physically connect to your iPhone to your computer upon booting the device.
Untethered jailbreaks are loved by folks who jailbreak their iOS devices, because they can keep all their jailbreak features and apps even in the event the they have to reboot their iPhone, iPad or iPod touch.