Pod2G, through his blog has told us about the progress of untethered JailBreak on iPhone 4S. He had previously confirmed about the iOS 5 untethered JailBreak working on other devices including iPad 1, iPhone 4, iPod4G etc. According to the iPhone hacker, his first attempt to implement untethered JailBreak on iPhone 4S has turned out to be unsuccessful and the reason is processor cache issues.
As per Pod2G, he is very close to the untethered JailBreak of iPhone 4S. Once he fixes these processor cache issues, the next step could be a proper working untethered JailBreak on iPhone 4S. It certainly has to do something with the cortex A9 cache management which is hindering in between the userland exploit founded by him. After figuring out what had gone wrong, we can hope for the success.
Anyhow, it is only a matter of chance. Pod2G has also informed that he would keep us updated with his progress tomorrow. In addition to it, you can also check out the Redsn0w update from DevTeam which allows you to do so much from the tool. We advise you to save your SHSH Blobs until Apple patch up the exploit unknowingly in the next software update. It would help you in the future.
Stay tuned!