[sidman]

Why not have them register with their first initial and last name or something of that sort.

The thing is, the old school forum site was on a YABB platform - for about 11 years now. In YABB you had a required filed in registration called "choose displayed name", which would be the field displayed on all posts/threads etc.
In addition we also urged members to type in displayed names alongwith batch year(year the person passed out from school) eg: Siddhartha Chaliha '91. This helped in users passing out the same year quickly identify posts made by their classmates.
I know we can have a custom field called 'batch year' in VB too, and postbit it, but the user name is the one that really stands out, apart from it being displayed on the 'who made last post' etc columns.