There's backups made every hour, I think, but there was something like ten hours between the attack and the admin logging in, so a lot of people had repaired the damage to their buildings and did other stuff in that time. The admin held a vote if people wanted to do a rollback, a small few (including myself) voted yes, but the vast majority voted no. The admin doesn't like doing rollbacks anyway. When I first joined on Saturday, they did a 2-hour rollback for some reason and a lot of people bitched at him because they lost some of their work. A 10-hour rollback would have annoyed a lot more people.