According to a recent report by Cisco, the traffic demands on the Internet will be doubling themselves every two years. The overwhelming majority of the traffic will be what they call “Visual Networking”, which factors in things such as IPTV and sites like YouTube. According to them, within 4 years Internet traffic will be around 552 exabytes, and shortly thereafter we'll need to start measuring in zettabytes, terms that most of us have never heard or dealt with. That's an extreme amount of traffic – and impacts us in many ways. ISPs are going to be delivering bandwidth to their end users and backbone providers will need to be able to supply it. From top to bottom, slow backbones and slow home connections are simply not going to cut it.
They don't indicate how long they foresee traffic doubling for, or give any indication as to when it would "plateau".