Redsn0w does a great job of jailbreaking any iOS device except for the iPad 2 but many users find that the process takes longer than it should because you have to download the entire .iPSW file that is specific to the device you want to jailbreak. With the latest update, MuscleNerd has addressed this issue and Redsn0w now detects and automatically downloads the essential files from Apple�s servers required to perform the jailbreak. It also stores these files in its cache which means you don�t have to download them again if you have to jailbreak your device again in the future. This new system is going to work for both tethered and untethered jailbreaks.
It is important to point out that the scan and store of essential files does not apply to the iOS 5 beta releases and those wishing to jailbreak iOS 5 beta will need to provide the full .iPSW files in order for it to work. There were a lot of fixes contained in this updated version of Redsn0w. Redsn0w 0.9.9b1 will jailbreak any device except for the iPad 2 which can be jailbroken on 4.3.3 using the JailbreakMe method.