Companies are diving in now, as they already feel burned by having missed out on the early explosions of the Internet. As far as the average user is concerned, the Internet's purpose is to distribute information and services. The Internet is not maintained by any one organization. Because it is a massive network of smaller networks which in turn contain smaller networks, the administration of the Internet is very distributed. If you have an Internet account with Sprint, your user account and the network you access to access the Internet is maintained by Sprint.
Sprint also owns some chunks of the major backbones that tie large networks together.
However, at some point, Sprint hooks up with other companies' networking resources so that they can exchange information with each other. The interesting part of this diagram is the fact that Internet usage is not expected to grow as rapidly as it has in the past. There are a number of reasons for this, but one of them is obvious - much of the huge growth of the first world has already happened. Additional growth is generally happening in the non-Western world and is not expected to propagate nearly as rapidly. Mind you, the Internet will still progress technically in a very aggressive fashion.