Contrary to many reports, iPhone 4S owners hoping for a future unlock should not update to iOS 5.0.1 but instead stay on iOS 5.0 to maximize their chances of an unlock.
MuscleNerd has confirmed to theiPhonenerd that an untethered iPhone 4S jailbreak for iOS 5.0 will be released at the same time as the iOS 5.0.1 jailbreak, or a day or two later. As always, for those looking to unlock, it is standard operating procedure to stay at the lowest possible baseband.
In fact, its recommended that those already on iOS 5.0.1 should check their build number and downgrade from build 9A406 to 9A405 while Apple is still signing both builds. Due to differences in the basebands, its more likely that an unlock will be found for the earlier build than the later. You can find direct firmware download links here.
We can’t guarantee an unlock will be found for iOS 5.0. However, in November MuscleNerd revealed that an unlock was looking ‘very promising‘ and was able to use an exploit to dump the baseband bootrom. However, it’s not clear if or when an unlock based on that exploit will materialize.