I just saw a press release that says that the developers of the iOS 4.2 jailbreak will have it ready by the time Apple officially releases iOS 4.2 to the public. They admit that there are still quite a few bugs to be worked out, but they have committed to the November release date and do not anticipate that it will cause any major problems.

They are so excited about this new software, that they have even hired the same advertising agency that McDonald's uses to come up with a new slogan for the software --

Jailbreak 4.2 "Because you deserve a brick today!"