I just followed through with this... got a message saying my number wasn't on the organizations list or authorized numbers or something like that but was able to follow a link and completed it under "Individual Responsibility" basically saying I was a member, employee, or student of Facebook. Obviously I'm a member, so I went forward, and I received a welcome to AT&T Premier pop-up screen.
I've already closed the screen, but it also made mention that this discount could be terminated at any time if it's determined that I'm not part of the Facebook organization and that it would take 2 billing cycles for any discounts to apply. So we'll see. If they give me AT&T gives me any grief, I'll just tell them that it said from the get-go members of the organization were welcome to the program, and that I am, in fact, a member of Facebook.