This reminder post is specifically and especially for iPhone 4s and iPad 2 users who have not updated to iOs 5.0.1 firmware but still using older version than the mentioned firmware. So this what BigBoss says!
unlock iPhone 4s of yours, that would be fine -- That means the 5.1 will close the door tightly for the A5 untethered jb once it's released.
So for both iPad 2 or iPhone 4s, drag your device to tastes iOS 5.0.1's offer A.S.A.P. If you really wish to untethered jailbreak it in the future. Update to using any methods, even via OTA update.
So restore to 5.0.1 immediately, once 5.1, there is no chance you can get to 5.0.1 from 5.0. Don't be stubborn, oke?:D
Update: It is already released, dubbed Absinthe, download Absinthe untethered jb for Windows, Mac and Linux. This is how to untethered iPhone 4s, iPad 2 jailbreak using Absinthe.