Twitter user JHackstar has tipped us off by a wiki showing picture that GreenPoison is not so far and is coming very soon which will support all devices.
The reason for new changes in Apple was to make improvement and close the doors of loophole for hackers which have been using until iOS 4.3. The waiting for the updates are over. It has been decided that GreenPoison will be released as it is, with a new confirmed at 4.3 to be made later. iPhone hacker Pod2g has also confirmed this on twitter.
Great news on 3 levels. 1st for sure many users were anxiously waiting for an untethered jailbreak on 4.2.1 since long time. 2nd, the GreenPoison will work on all hardware and finally the release is not far away.