Yes! The 5.0.1 iPhone 4S untethered jailbreak release is finally close due to the fact that significant progress has been made. Unsigned code is now running on the device on which the jailbreak developing dream team has been working with.
The 5.0.1 iPhone 4S untethered jailbreak is based on the exploits discovered single-handedly by p0d2g. That particular exploit is already being used to jailbreak iOS 5.0.1 untethered on non-iPhone 4S devices. P0d2g had run in to some issues with iPhone 4S, iPad 2 iOS 5.0.1 untethered jailbreak but he was soon joined by legandary jailbreak gurus MuscleNerd, Planetbeing and P0sixninja. The four combined have been able to make substantial progress in a surprisingly short span of time.
One of the amazing things these guys are doing includes updating the public on jailbreak status. Planetbeing has sent out updates regarding 5.0.1 iPhone 4S untethered jailbreak twice during last couple of weeks. Merely hours ago he tweeted another update, which says:
Finally got unsigned code running on my 4S with the stuff that will go into the new jailbreak!
There's a reason why it is so hard to jailbreak A5 based devices such as iPad 2 and iPhone 4S as compared to older A4 based devices. This particular processor, A5, is not susceptible to the Limera1n bootrom exploit. Devices that have this processor can only be jailbroken using a userland, which is a software based one, exploit unless and until someone dumps the A5 bootrom. Be advised though that it has nearly been an year since the release of A5 based iPad 2 and no one has been able to dump the A5 bootrom. While this tweet does indicate that significant progress has been made, it will still take some time before the iPhone 4S, iPad 2 iOS 5.0.1 untethered jailbreak is ready for public release.
We'll keep updating you as soon as more information comes in regarding 5.0.1 iPhone 4S untethered jailbreak. Let's keep hoping for an early release!