Redsn0w 0.9.5 beta has been released to jailbreak iOS 4 (iPhone OS 4). It supports iPod Touch 2G too. It enables Multitasking and Home screen wallpaper for iPod Touch 2G.
This release of redsn0w is a beta and hence does not hactivate. Also, do not go near this if you need unlock. This release is suitable only developers. Also you need iTunes 9.2 which is only available on mac. Hence it is a Mac only release.
The steps remains the same. Please check out this guide for a step by step instructions: Step by step guide.
Remember, this jailbreak is intended for developers only and you won’t be able to unlock as of now. Do not upgrade if you need carrier unlock.