A recent tweet by Pod2g confirms that the much awaited GreenPois0n RC5 for Windows to untether iOS 4.2.1 jailbreak tool is now finally out and available for download. This means that you can Jailbreak any iOS device using the Windows version. It is the same process for any Windows user as done by any Mac OS X user. You can grab hold of the Windows Version here (Keep refreshing the link if it doesn’t download as the server is on load this time).
Another great news by Pod2g is that GreenPois0n RC6 for Apple TV 2G would also bring Untethered Jailbreak is also coming real soon.