MuscleNerd had just confirmed that the iPad 2 and iPhone 4S Bootrom are the same version which is iBoot-838.3.
That means the possibility of having untethered jailbreak for iPhone 4S is high.
Post from my iPhone
redsn0w has been updated to 0.9.9b3 to auto-detect iOS5 GM firmware. Remember: it’s still tethered for all devices except for iPhone 3GS with old bootrom. If you don’t useredsn0w to “Just boot” at power up, all jailbreak apps (and even some native ones like MobileSafari) will fail to launch.If you already jailbroke the GM by pointing an older redsn0w at the beta7 IPSW, there’s no need to re-run the full jailbreak step again…just use this newer one to make the tethered boot easier