Nothing really, although I imagine if a particular instance was getting overrun with bots the admin or mods would probably step in and possible prevent new accounts from signing up or something
zeldis
Ironically I remember it bringing me to reddit a few times and I did not like it at all at the time haha. I just wanted to see more crazy websites and read the SU comments. It was always fun to find yourself on some website through some other means, and then checking to see if there was any comments about it on stumble upon and being pleasantly surprised when there was
newgrounds (The Impossible Quiz, anyone remember the square root of an onion?), Numa Numa, The Evolution of Dance, Shortbits 2, Badger Badger Badger (and other Weebl animations), Onyxia Wipe Animation, bash.org, Stumble Upon (a useful toolbar?!), all sorts of great stuff from that time
Honestly, this does seem like the better way to go. Back in the myspace days, we probably should have gone down this route instead of jumping ship to facebook. It would have been really cool to see how things would have turned out if it had been federated between universities from the get-go
Old School RuneScape