The iPhone Dev team said on Friday that, for now, the iPhone 2.2 software, still in beta, remains susceptible to jailbreaking on all but the iPhone 3G and iPod touch 2G.
Do demonstrate what’s been achieved, the team showed the terminal app open on an iPhone 2G running the 2.2 beta. Their blog noted, “Hardware already vulnerable to pwnage remains vulnerable in version 2.2.” 
Source: iPhone Dev Team
Of course, Apple may still have some surprises in store for the release version, but for now there’s optimism that the technology of the PwnageTool will remain able to jailbreak and unlock the hardware and software of the iPhone 2G and iPod touch 1G.