We finally got an untethered jailbreak for iPhone 4S and iPad 2 yesterday via Greenpois0n Absinthe. Until now the tool was only released for Mac users. It has now been updated with support for Windows users.
If you haven't already jailbroken your device via redsn0w CLI 0.4.3, I'd recommend using this method. Hit the links below for instructions and a download link.