Look at how computers have changed within the last 20 years! So much has changed about them. Back in the day it was always dial-up , now we have Wi-fi !
But think about it this way..
There's always something really big in history that has failed , right?
Human's always used pagers back in the 90's to keep in touch with others. And now in 2012 we use Cell Phones to keep in touch!
Or use mp3 players as an example. About 5 years ago mp3 players were really big, and now the big thing is "Ipods" or any Apple device for that matter.
The internet is a big thing, trust me! But sooner or later, there will be something to replace it. Maybe replacing the internet won't be so bad.
Maybe we'll be able to have internet in our brain's some how.
Technology is always getting bigger, and you never know what's going to come next.