An untethered jaibreak for the new iPad (3) was ready in less than 24 hours since it's launch thanks to iOS hacker Stefen Esser aka i0n1c.i0n1c is known for his work on jailbreaking iOS 4.3.3 and while he hasnt been very active since then, it looks like he is making a comeback where it matters.
He has posted a video which demonstrates the untethered jailbreak on the new iPad
Unfortunately the untethered jailbreak for the new iPad is still not ready for public consumption. But the video shows that we will be able to enjoy the advantages of jailbreaking on the new iPad sooner, rather than later.
source : Jailbreak-Untethered