Limera1n can do this! Yes, it can jailbreak iPod touch 4G, iPod touch 3G, iPhone 4, iPhone 3GS and iPad on iOS 4.1 / 3.2.2. By the way, it still not working with old bootrom devices, Geohot is fixing the issues right now. So, here's a quick how to guide to jailbreak your iPod touch 4G, 3G running iOS 4.1 using Limera1n.
You can follow the same step by step
guide instructions (geohot's official blog) to jailbreak iPhone 4. It's the same guide for iPod touch 4G and iPod touch 3G. Just to let you know, iPod touch 2G is jailbroken with Redsn0w and still tethered until Comex release his userland exploit.
