MuscleNerd of the iPhone Dev Team just revealed a preliminary iPhone 4S jailbreak through pictures he posted on his Twitter. A public release date has not been given.
Immediately after iPhone 4S was launched we discussed the possibility of iPhone 4S untethered and tethered jailbreak in detail. We mentioned that it was likely for an iPhone 4S jailbreak to be made available soon keeping in mind the fact that simply a userland exploit was needed to be found in iOS 5 even if the developers were not able to dump the A5 bootrom which would allow for a lasting jailbreak that Apple would not be able to fix through a software update.
MuscleNerd has revealed that the iPhone Dev Team is hard at work for developing iPhone 4S jailbreak and so far what they have been able to do is achieve a jailbreak in preliminary stage. He did not reveal whether this was an iPhone 4S untethered jailbreak or a tethered one, or they had been able to dump the A5 bootrom. What he did reveal was that this jailbreak, when made public, would be compatible with iPad 2 as well.
Don't expect the public release of iPhone 4S jailbreak any time soon though. As we previously mentioned, this jailbreak is still in preliminary stage, just a subtle foot in the door. There are huge pieces missing which require a lot of work before this iPhone 4S jailbreak is made stable enough for public release. MuscleNerd has hinted that there are big hurdles in their way which need to be removed before releasing this new iPhone 4S jailbreak as well as iPad 2 jailbreak to the public.
Nothing's confirmed just yet, this new iPhone 4S jailbreak can either be through a bootrom exploit or a userland exploit. In both cases, there's a possibility that this jailbreak can be untethered. In the case of userland exploit, it would be possible for Apple to easily patch the iPhone 4S jailbreak by releasing a new software update. Bootrom exploits are not easy to patch as they require the hardware, processor to be exact, be changed.
On the other hand we still wait for word from the Chronic Dev Team camp. They revealed earlier last month that they had managed to find five new userland exploits that could be used for iPhone 4S jailbreak as well as iPad 2 jailbreak on iOS 5 firmware. We know that they're hard at work too, let's just see who succeeds in releasing iPhone 4S jailbreak to the public first.