The Internet is the ultimate mating ground for ideas, the supreme lekking arena for memes. Cultural and intellectual evolution depends on sex just as much as biological evolution does; otherwise it remains a merely vertical transmission system. Sex allows creatures to draw upon mutations that happen anywhere in their species. The Internet allows people to draw upon ideas that occur to anybody in the world. Radio and printing did this too, and so did writing, and before that language, but the Internet has made it fast and furious.
Exchange and specialization are what makes cultural evolution happen, and the Internet's capacity for encouraging exchange encourages specialization too. Somebody somewhere knows the answer to any question I care to ask, and it is much easier to find him or her. Often it is an amateur, outside journalism or academia, who just happens to have a piece of knowledge to hand. An example: suspicious of the claim that warm seas (as opposed to rapidly warming seas) would kill off coral reefs, I surfed the Net till I found the answer to the following question: is there any part of the oceans that is too hot for corals to grow? One answer lay in a blog comment from a diver just back from the Iranian side of the Persian Gulf where he had seen diverse and flourishing coral reefs in 35C water (ten degrees warmer than much of the Great Barrier Reef).
This has changed the way I think about human intelligence. I've never had much time for the academic obsession with intelligence. Highly intelligent people are sometimes remarkably stupid; stupid people sometimes make better leaders than clever ones. And so on. The reason, I realize, is that human intelligence is a collective phenomenon. If they exchange and specialize, a group of 50 dull-witted people can have a far higher collective intelligence than 50 brilliant people who don't. So that's why it is utterly irrelevant if one race turns out to have higher IQ than another, or one company hires people with higher IQs than another. I would rather be marooned on a desert island with a diverse group of mediocre people who know how to communicate, from a singer to a plumber, say, than with a bunch of geniuses.
The Internet is the latest and best expression of the collective nature of human intelligence.