On Friday evening, I discovered that the site was offline and inaccessible. I tried restarting the server, but it couldn't boot. The hosting company installed a new HD and put the old HD in to alow any data recovery. Unfortunately, all the home directories and backups on the drive appeared to be gone. Simultaneously, I began the slow process of uploading the rather large backup of the site and restoring it from backup.
That backup appears to have been a late January backup, unfortunately. I thought I had a backup created after restoring from the earlire attack, but it looks like I don't. I'm going to double-check when I get home--I am out of town over the weekend (Great time for the site to go down, eh?!)--but I suspect this is it. Mea culpa!
Things like this aren't all bad. It provides a strong incentive to have an off-site backup strategy (daily backups are kept on the server, and I periodically download a daily backup to my desktop machine), and that's something I will be thinking more about in the coming days, probably automating some kind of FTP backup. I'll also be re-upgrading the BB to the latest vBulletin version when I get home.
Sorry for your lost posts (or accounts, for those of you who recently registered) and the confusion that this has caused by my absence when the site came back online.