Four Island

iOS 4.2.1 (not iOS 4.2--that was never released because it had quite a few holes in it) for iPhone, iPod touch and iPad was released today! This brings AirPrint and AirPlay to all devices as well as multitasking and folders to the iPad! While this certainly is a great upgrade (especially if you have a Mac and have used the AirPrint Hactivator which will allow you to AirPrint to any printer that is shared by the hactivated Mac (otherwise you're restricted to a very limited number of HP printers)), we warn you:

IF YOU RELY ON A JAILBREAK OR UNLOCK, DO NOT UPGRADE YET.

Yes, while you may have a pwned-for-life device, if you want an untethered jailbreak, you're going to have to wait a bit. However cool AirPrint is going to be, I don't think it's worth giving up your jailbreak for any period of time. This may be different for the iPad--multitasking is a pretty big feature and it may possibly be worth it to some people to give up their jailbreak for a while so that they can enjoy these iOS 4 features, but if I had an iPad myself, I'd just install Backgrounder and get on with it. Don't upgrade if you want to keep your jailbreak. Just wait, and hopefully the awesome people behind the jailbreaking scene wil release a new tool or a new version of a tool that can jailbreak iOS 4.2.1 in short time.