Ive noticed as my friends list grew from 100 to over 1000 over the years.. I update my status less and less specially the more personal they are.. as my facebook friends list consist of acquaintances and friends of all backgrounds --
Facebook for me now has just become a social rolodex, a collection of people I've met over the years.
Could I post about something funny that happens at a bar on a friday night out on town? Sure! Do I think twice? Yeah, how would colleagues view it / business acquaintances (as I tend to view everyone as a "friend" no matter how long I've known them for)
Something exclusive for just my grad class or those in my immediate or near immediate (weekend friends / friends to go on trips with) would be nice in a simplified, less feature filled site service.