Update #3: *For those Mac users with an old-bootrom 3GS who really know what theyre doing, heres a minimal 3GS 4.2.1 bundle that will get you to 4.2.1 without updating your baseband. *Be sure to uncheck Activate the iPhone using Expert mode. *To actually jailbreak after youve restored with the help of that bundle, please use redsn0w. *If you dont know how to drop a bundle into PwnageTool.app, please hold off on 4.2.1 until its untethered for everyone (or wait for a nice tutorial from somewhere like http://iclarified.com)
Does this result in an untethered jailbreak for us old bottom folks?