Sometimes it pays to sit back from the bleeding edge a little. Like when the Dev Team releases their PwnageTool for iPhone 3.1, and it doesn't work on the iPhone 3GS or the new Touch. All in due time, people!
No, really, you won't have to wait long. From the Dev Team:
Because of changes with Apple's update techniques this will be a multipart release, starting with the initial release of PwnageTool for Mac OS X - this application supports the iPhone 1st Generation (2G), The iPhone 3G and the iPod touch 1G. NB: THIS DOES NOT SUPPORT THE 3GS OR 2ND or 3RD GEN IPOD TOUCH. redsn0w for Mac OS X and Windows will follow sometime in the near future, please don't bug us about it - we'll release when we have something ready.
The rest of you can download PwnageTool right here, which should handily jailbreak and unlock anything piece of hardware that hasn't been released in the last four months. [Dev Team—Thanks, tipsters!]