To sum up his post, his take on the situation is that the Internet facilitiates conversations between people, which are inherently more interesting than the Old Media model of "We talk, you listen" which is what drives all of the MSM from newspapers to magazines to books to movies and TV. Radio, too, for that matter, although talk radio doesn't fit the template for reasons I'll discuss below the cut.
Talk radio is interactive - there is a host, and on most programs he or she drives the show by setting the tone and deciding what the topic of the day will be. This makes it different from most radio, which plays music or is otherwise broadcasting something that (they hope) a lot of people are interested in, which is where Arbitron and Nielsen come in - while they're pretty crude tools, they're all that broadcast media has to measure the audience for a particular show. DJs who play requests aren't really different from the standard broadcat model, because most of them have a playlist dictated by the program director and won't necessarily play what you want to hear, which is why I don't bother calling K102 asking to hear Jason & The Scorchers or James McMurtry. It'd be a waste of my time and theirs.
All the other Old Media are similar one-way monologues, with the author/director/editor telling his story the way he wants to tell it. Your reaction doesn't affect the book/movie/newspaper, except possibly to appear in a "Letters" column days after the fact in edited form. Worst of all, until fairly recently (and with the exception of books), the stories were time-locked. You saw the movie when it was showing in the local theaters, and if it only played in a handful of theaters in New York and LA while you lived in Des Moines, you were just out of luck. Maybe months later it would percolate out to an art theater, if your city had one. Maybe not. Maybe it would be shown late at night on a local TV station; maybe not.
Things changed somewhat when tape recorders and VCRs showed up. Now you could listen to music all mixed up the way you wanted it, if you were willing to take the time to make your own tapes off the records you and your friends owned. Maybe you'd be daringly experimental and use your tape recorder to produce assembled music of your own, in a low-tech precursor to digital sampling. (You can hear some of this music on the local radio show Some Assembly Required.) Maybe not; most people were perfectly happy to buy pre-recorded cassettes and shove them in their cars' tape decks or those newfangled Sony Walkman gizmos. Still, most media was produced "on high" (sometimes literally, if you look too closely at Hollywood and the music bidness) and cast into the marketplace with more or less hype depending on how hard the given show or band was being pushed by the Powers That Be.
The internet has changed this, and predictably the Old Media are screaming their heads off about intellectual property theft and irresponsible bloggers daring to criticize their betters regarding the media's failure to cover what the blogosphere felt was important. Digital technology has also brought us the abilitiy to sanitize PG-13 and R-rated movies, much to the annoyance of directors who don't want people seeing movie the way the people want to see them, but rather as the director wants them seen.
It's not just the Internet, although the Internet is certainly a great enabling technology, enabling P2P networks to spead like wildfire even as the entertainment industry's lawyers choke the life out of client/server file sharing networks like the original Napster. Computer games (including those made for gaming consoles such as the Sony Playstation and Microsoft XBox) allow people to write their own stories without the clunkiness of the "Choose Your Own Story" books or the early text-based RPGs; the Internet allows people to play the games together, often in massive multiplayer games that practically form their own subcultures. I think that in that particular arena Jarvis is right, and the small conversations that make up the MMORPGs will continue to be popular and profitable for the companies that sponsor them. Will they kill off books and television and movies? Unlikely; we still have radio and movies, long after many pundits confidently predicted that both would be superseded by TV. For that matter, radio and movies were supposed to be the death of theater, but nonetheless community and city theaters across the country still stage plays for the pleasure of their audiences.
It wouldn't surprise me if some enterprising Hollywood type woke up to the possibilities offered by MMORPGs. Reality shows are popular; what if instead of the annoying "Big Brother" and "Survivor" we were treated to a story about a group of people engaged in an adventure through a fantasy world? What if we got to see local teams duking it out in the simulated hedgrows of France - or New Jersey?
John W. Campbell once derided fiction as being limited "merely" to the present and past of man, whereas science fiction could tell stories from the creation of the universe to its end, and in parallel universes to boot. With the Internet and increasingly powerful computers that can drive more and more realistic depictions of fantasy worlds, science fiction may be ready to go live in a way that Campbell and his Golden Age authors could only dream of.