Questions, questions, questions.
And no answer, whatsoever. Apart from some claims about DDoS attacks, but nobody really believes this anyway. Even if it were true.
But, whoever they are, WikiLeaks appears to be stronger. The URL under which the secret-revealing website can now be found is with their new Swiss top-level domain name (TLD) http://wikileaks.ch/ which redirects to an IP address: 184.108.40.206
To my best estimation, it's only a matter of time before WikiLeaks will be able to point the main domain to the proper IP address again. Perhaps they could get a little bit of help from OpenDNS, GoogleDNS end some other (free) DNS server providers as these companies would be technically able to just return the IP address on queries to wikileaks.org.
Will it be only a matter of time before they strike again? Who knows?
Update: The Swiss site already appears down. Currently, the whistle-blower site is available through:
Update dec 6: The team behind WikiLeaks has published a list of over 200 locations where there content has been mirrored: wikileaks.ch/(..)/mirrors.html along with instructions on how to help out with setting up your own WikiLeaks mirror server wikileaks.ch/(..)/ass-mirror.html