Geohot's Limerain was released on Sunday creating a stir in the whole jailbreak community. It uses a different exploit from Chronic Dev-Team's SHAtter, releasing Greenpois0n today would have burned those 2 exploits away to Apple to patch in an update. The Chronic Dev-Team have postponed the release of Greenpois0n in order to include the new exploit found by Geohot.

Here is a word from the Chronic Dev-Team : 

Thanks to the irresponsible antics of geohot, we will have to delay the release of greenpois0n (new ETA = as soon as possible), so that we have time to clean up his little mess and integrate the exploit he uses in limera1n into greenpois0n. This way, we can save SHAtter for future devices that may still be vulnerable to it.
We know that this is not what some people want to hear, but due to geohot needing to feed his ego (as usual) and revealing his limera1n exploit, we do not have any other responsible options.

As always, don't forget to give your views on the issue.