Wikileaks is currently offline supposedly due to their host being hammered by DDOS all this week. More on Reddit
here and an article about it
here.
EDIT: This should be fine, in the long run, for the record. They should be able to change the nameservers to a different host (or transfer the domain name, whichever is the case) no problem. It's kind of Wikileaks bad of they really did notify them of problems beforehand.