The most successful prophecy I know in science fiction is in E.M. Forster's "The Machine Stops".
"Very well. Let us talk, I will isolate myself. I do not expect anything important will happen for the next five minutes — for I can give you fully five minutes, Kuno. Then I must deliver my lecture on 'Music during the Australian Period'."
She touched the isolation knob, so that no one else could speak to her. Then she touched the lighting apparatus, and the little room was plunged into darkness.
"Be quick!" She called, her irritation returning. "Be quick, Kuno; here I am in the dark wasting my time."
[contents of a videophone call elided]
Vashanti's next move was to turn off the isolation switch, and all the accumulations of the last three minutes burst upon her. The room was filled with the noise of bells, and speaking-tubes. What was the new food like? Could she recommend it? Has she had any ideas lately? Might one tell her one's own ideas? Would she make an engagement to visit the public nurseries at an early date? — say this day month.
To most of these questions she replied with irritation — a growing quality in that accelerated age. She said that the new food was horrible. That she could not visit the public nurseries through press of engagements. That she had no ideas of her own but had just been told one — that four stars and three in the middle were like a man: she doubted there was much in it. Then she switched off her correspondents, for it was time to deliver her lecture on Australian music.
I first encountered this story in a course in "Post-Modern Literature and Science" taught by David Porush at dear old RPI. He gave it to us without context and challenged us to guess its year of publication, correctly confident that foreknowledge of Forster's oeuvre wouldn't significantly prejudice the results from a bunch of RPI undergrads.
I guessed 1910; the correct year is 1909. I was tipped off by its opening:
Imagine, if you can, a small room, hexagonal in shape, like the cell of a bee. It is lighted neither by window nor by lamp, yet it is filled with a soft radiance. There are no apertures for ventilation, yet the air is fresh. There are no musical instruments, and yet, at the moment that my meditation opens, this room is throbbing with melodious sounds.
He didn't have a word for the artificial production of music. I was surprised to hear others in the class guess as late as 1960.
So almost a century ago, Forster not only anticipated the Web, but the anxiety of Internet withdrawal — when the closest analog I can think of would have been trying to keep on top of all the newspapers and new books in London (which I don't doubt would have been daunting.)
Revisiting the story now, I'm even more impressed by the degree to which it anticipates blogging, with everyone sharing their opinions, and placing great weight on their responsibility to maintain their output... independently of whether they have anything to say.
It's a relief to get this out — I hadn't updated my blog in a day and a half!