We finally have some good news for the jailbreakers. P0sixninja has tweeted that they are about to release the GreenPois0n jailbreak. According to P0sixninja, this day will be Sunday at 10:10 AM GMT. If P0sixninja is right, all of you who are waiting for an iOS 4.1 jailbreak will finally be able to jailbreak your iDevice. Though Chronic Dev-Team hasn't announced whether the jailbreak will be tethered or untethered, but it looks like it will be an untethered jailbreak.

Please remember that like all programs being developed, things can come up to extend this ETA. While P0sixninja himself said it will be released this Sunday, so don’t be surprised if things change.

SHAtter is the bootrom exploit discovered by Pod2G, a former member of the Chronic Dev-Team. A bootrom exploit is a low level exploit that can’t be fixed by Apple with a software update like it did with iOS 4.0.2 to patch the security hole used by JailbreakMe.

Apple can prevent jailbreaking, by releasing iDevices with a new bootrom that patches the exploit, but Apple won’t be able to stop users from jailbreaking devices with the older bootrom. So GreenPois0n which makes use of the SHAtter exploit will jailbreak all existing iDevices for life.

Update (10/8/2010) :

GreenPois0n will not work on older iDevices like - iPhone 3GS, iPhone 3G and iPod Touch 3G. It will work only on devices that have Apple's A4 processor so it will be compatible only with iPhone 4, iPod Touch 4G, iPad and the new Apple TV.