There have been connectivity issues for some of our services, so we’ve been given a new IP, and I did not know this beforehand (there are other admins for this specific dedicated server, too).
Give it an hour to let your DNS changes replicate, or you can also try to manually flush your dns (http://www.tech-faq.com/how-to-flush-dns.html).
The short version is: wait an hour or two and you should be able to play again.
Sorry about the plethora of problems that has sprung up lately. :\