greenpois0n only works on firmware 4.1, so (only if you have an iPhone 4!) if you are on a lower firmware make sure you use TinyUmbrella to preserve your baseband.
I think this dont work, i tried on mine and it turns off then it took a lot of time to come back, i thought... OMFG :O but then it turns on again. so i dont recomend it yet
i went through the process and it said that i'm jailbroken. but cydia isn't working. when i open cydia, it's a blank screen. any body know what's going on?
yeah, i had the same thing....it went dead for like 5 minutes and wouldn't turn on even if i press the power button. i got scared and unplugged it and plugged it back on again; restarted greenpoison and just let it stay connected for another 5 minutes or so and it turned on by itself and said jailbreak was complete. so don't worry.