That is, a good model of changing fashion are some forerunners that starts doing something -- and then gets copied by lots of people. The ones that want to be fashionable then have to change or look like all others.
Technical news sites seems to be places with interesting discussion that gets overrun with wannabees that lowers the average quality. If this is correct, HN is doomed to be Diggified (the opposite of dignified). Like all non-invitation discussion sites.
(-: I also tried to be responsible for the average quality and only read, but now failed to keep my fingers controlled after a few months. :-)