"This is due to a hardware problem with one of our servers. We are working with our host to rectify the situation and bring the sites back online as soon as possible." --vbulletin.com
Thanks for that clarification. How'd you know, though? I see a blank page or error when I try to visit the site.
They were brought together a year or so ago. Even username/passwords are now shared between them. I wouldn't be suprised to hear that they are on the same server(s)