Just now Corona untether jailbreak is updated to v.1.0-8 which includes iBooks image loading bugs fix for iPhone 4S running over iOS 5, whereas few hours ago Corona 1.0-7 was also released to resolve the same issue but that was still buggy.
See also:
How to Do Untethered Jailbreak of iOS 5.0.1 with Corona
How to Jailbreak iOS 5.0.1 with RedSn0w
How to Do Untethered Jailbreak of iOS 5.0.1 with PwnageTool 5.0.1
How to Jailbreak iOS 5.0.1 with Ac1dSn0w
Saurik from Cydia has highly recommended Corona v.1.0-8 for users who have already jailbroken their iPhone 4S and iPad 2.
To install latest Corona visit Cydia on your jailbroken iDevice.