The iPhone Dev Team iPhone hacking group released their PwnageTool 2.0 unlocking and jailbreaking tool for iPhone Software update 2.0.
As reported the PwnageTool 2.0 is not able to unlock the iPhone 3G, just jailbreak it.
PwnageTool 2.0 unlocks though the old iPhone with the new firmware 2.0.
The iPhone Dev Team site has links to several mirrors to download the PwnageTool 2.0.
There is no word yet on when the group will release a version of PwnageTool that will also unlock the iPhone 3G.