Sn0wbreeze 2.1 Jailbreak tool for iOS 4.1 and iOS 4.2 is coming very soon. All the work on Sn0wbreeze 2.1 has been implemented and is going to be available in coming days. At the moment, the tool is under testing process for any existing bugs. The update on Sn0wbreeze has been provided by iH8sn0w.
According to iH8sn0w, Sn0wbreeze 2.1 to Jailbreak iOS 4.1 and iOS 4.2 uses the latest Limera1n exploit. For older devices it uses steak4sauce.
As we know that Cydia still does not work for iOS 4.2, so applications cannot be installed currently. Update:New Updated Version Of Upcoming Cydia Jailbreak is Now Ready iOS 4.2
For the people who are still now aware of this tool, Sn0wbreeze Jailbreak allows you to create ustom .ipsw files on windows like Pwnage Tool which creates custom .ipsw files on Mac.
Remember that you need to save SHSH blobs using TinyUmbrella if you want to use Sn0wbreeze 2.1 to jailbreak your device.