iPhone news of the day, PwnageTool 2.0 is out. See http://blog.iphone-dev.org/ for download links.
I've just unlocked my 1st-Gen iPhone running v2.0 firmware (official release, build 347) to run on Vodafone NZ. Previously this had only been possible with firmware 1.1.4 and a few of the early 2.0 betas.
FYI: PwnageTool 2.0 also activates and jailbreaks iPhone 3G, so that you can install custom software on it BUT there is presently no iPhone 3G unlock. This is likely to take a few weeks since the baseband chip in the iPhone 3G is new. Not that you really need an unlock on the iPhone 3G in NZ at the moment.
Download it and happy upgrading and unlocking!