The new jailbreak tool 'Greenpois0n' has been released for iOS 4.2.1.
Just finished jailbreaking the iPad and all is well.
It's a little complicated but nothing any primate with 2 thumbs and a PC can't accomplish.
How To: Jailbreak iPad Using Greenpois0n RC5 For Windows [Full Guide] - GreenPois0n.Us
If you are interested and need any help, just let me know.