It has been subject to a denial of service attack, apparently. Those who live by the hack will die by the hack.

From here:

What goes around comes around: Someone is hacking the hacktivist. And it may be none other than the hacktivist himself.

A self-described patriotic hacktivist known as “The Jester” — who has garnered a reputation for taking down jihadist websites and is believed by those familiar with his work to be responsible for taking WikiLeaks offline during its recent dump of State Department cables — is claiming to be the victim himself of an online impostor trying to cash in on his name.

But that’s hardly all there is to the story.

The Jester — who describes himself online as a “Hacktivist for good. Obstructing the lines of communication for terrorists, sympathizers, fixers, facilitators, oppressive regimes and other general bad guys.” — says he’s “an ex-soldier with a rather famous unit, country purposely not specified.”

Following that ignominious rout, the DNS provider for Wikileaks has terminated the domain name:

The WikiLeaks website has been taken off on Thursday, Dec 2 after its domain host provider EveryDNS.net terminated its account.
The whistle-blowing website WikiLeaks has told in its Twitter account that, “WikiLeaks.org domain killed by US everydns.net after claimed mass attacks.”

h/t to my underpaid research assistant.