It seems we dropped out of DNS for a few minutes on Saturday evening (10pm on the 7th Jan). I'm afraid this was due to a DDOS attack on our DNS service provide.
More information can be found here:
http://blog.easydns.org/2012/01/08/mini-faq-about-the-jan-07-ddos-attack/
We are now implementing a solution to ensure this doesn't happen again. (Multiple DNS providers). We do apologies for the problems this caused.