I have personally Jailbroken my iPod Touch and my iPad and enjoy the choices the process provides. I used the JailBreakMe.com site to JailBreak my iPod Touch and my iPad. I actually have Jailbroken my iPad three more additional times, using three different processes. I originally used Spiritjb.com, then Limera1n and lastly Greenpois0n. I helped a co-worker re-JailBreak hers iPad with Greenpois1n and then had to reload the Cydia app with yet a fourth process called Redsn0w. Why so many different ways to JailBreak iOS devices? Well Apple is determined to prevent the JailBreaking process from happening or reoccurring, so the developers' product may cease to work up to a certain iOS version.
The JailBreak process you use is really based on what the iOS version you have on your device. Additionally you want an untethered Jailbreak where you can reboot your device at will, versus a tethered Jailbreak where you would have to connect to a desktop in order to re-Jailbreak the device after a reboot.
GreenPois0n is currently the latest one to allow the latest version of Apple's iOS to be JailBroken; including the Apple TV 2. The GreenPois0n RC6 download is now available for public consumption, should you want it. This particular version of GreenPois0n brings with it untethered jailbreaks for the AT&T iPhone, Verizon iPhone, iPod touch, iPad and now the Apple TV 2.
The procedure for jailbreaking your devices hasn’t changed in the lastest RC candidate, so if you’ve done a GreenPois0n install before, this one will be right up your alley.
You can now download GreenPois0n for the Mac and Windows.
Related: After you JailBreak your iPad. be sure to check out my best Cydia apps for the iPad.