Common questions
Why?
There is no easier or faster way to jailbreak/activate/unlock than to get iTunes to do it for you during what it thinks is a normal update.
Does it work on 1.2.0?
Yes. In fact it's the only way to jailbreak 1.2.0 and beyond, since Apple fixed the ramdisk hole.
Is it reversible?
Yes, every part of pwnage is easily reversible simply by restoring to an official Apple ipsw instead of your custom ones.
Can Apple close this hole?
Please visit the technical Pwnage page to see how the entire chain of trust in the boot process has been compromised.