The Encyclopaedia Britannica As We Know It has existed from, say, the
ninth edition (1889) to the present, and is probably in sharp decline
now. Let's say it's had about a 150-year life. I don't think it has
another twenty years in it. And I don't think the Boston Globe will
be available as smudgy ink on pulp paper delivered to front porches
in twenty years, either...
The slide rule as we know it--as a working tool for engineers--lasted
from about 1860 into the 1970s... a bit over a century.
Carbon paper... didn't really come into its own until the invention
of the typewriter... it's lasted a bit over a century, too.
"New media" though, have had a shorter life.
The text adventure game: Colossal Cave, early 1970s, to about 1990
and the folding of Infocom. About twenty years?
The soap opera: 1930 to present. The _radio_ soap opera, though,
obviously had a much shorter life. Thirty years?
Wikipedia is much harder to predict, though, because it is changing
over time and will continue to do so. I'd give good odds that ten
years from now there will be a recognizable "website" on something
called the "Internet" named "Wikipedia" that will be an online
encyclopedia, but I wouldn't bet that its culture and policies will
be closely similar to those in existence today.