[nights] Like everything, it's been mostly full of crap since it started, but it's only been in the last few years that the crap has expressed a desire to leap down everyone's throat.
The big cautionary tale of the net is Usenet, which although some people manage to keep active newsgroups going (using I don't know what antispam measures), is now almost entirely spam. I've been working recently on a little predator/prey population interactives, and I wonder if the cycles of spam-genuine content follow a similar statistical pattern. i.e. the population of predators increases, diminishing the population of prey, which in turn leads to extinction for the predators...