In a post on the notorious message board 4chan, a person claiming to represent the group said that the DDoS attack was designed to "send [Minecraft creator Markus Persson] a clear message of how the future of Minecraft will turn out unless he gets to work, namely by influencing the amount of sales taking place, due to the attacks."
On his blog, Persson has stated that he's "signed up for a DDoS protection service, and took the chance to upgrade the server hardware to a much more powerful beast." The latter is still a work in progress. "I haven't migrated things over to that server yet, but that's coming soon," he wrote.
We're sure someone will recreate the whole sordid event in Minecraft soon enough.