Get limera1n from www.limera1n.com.
Run it, follow instructions, (super easy) will jailbreak your idevices for LIFE.
This does not work for iPhone 3gs (new bootrom)!
ALL versions of iDevices supported! Screenshots shown below for ipad, iphone4, iphone3gs.
In the mean time greenpois0n has been delayed. dev team says “The release of limera1n has (hopefully!) averted the burning of 2 bootrom holes at once (both his and SHAtter). Releasing SHAtter now would be a complete waste of a perfectly good bootrom hole in light of limera1n, and so it can be held until Apple closes limera1n’s hole”.