One of the Cydia repositories, BigBoss has also announced the need to update to iOS 5.0.1:
Apple is due to release 5.1 soon. When that happens, they will stop signing 5.0.1. This means you will only be able to restore to 5.1. 5.1 breaks the upcoming jailbreak. If you are currently a 4s owner or an ipad 2 owner, you will want to get your device to 5.0.1 ASAP. This way when the jailbreak is released, you will be able to use it. If you do not restore to 5.0.1 now, in a few days when 5.1 is out, you may never be able to get from 5.0 to 5.0.1 and only option will be to wait again.
The current version is iOS 5.0.1 and is available when you connect your iDevice to iTunes or update your Software OTA. You may leave yourself out of the imminent corona jailbreak if you ignore this (again).