We're long past the days when you can pickup the phone and ask the operator to connect you to "Pennsyvania 6-5000". However, the Internet is starting to feel old in that way—we're running out of addresses for the Internet Protocol Version 4—yes, those numbers like 192.168.1.1 that one encounters when setting up a home network. In 700 days there won't be anymore—so we need to move to IP version 6. This move has analogies in the Digital TV transition and the addition of area codes to the phone network a few years ago.
There are big blocks of these numbers that ISPs like AT&T are allocated to use by ARIN, the American Registry for Internet Numbers (and 4 other global RINs around the world). IPv4 is 32bits—4 billion possible numbers—but that's not enough, according to ARIN CEO John Curran. He's working to get people to adopt IPv6.
In the following video interview by Howard Greenstein, John describes the situation and gives some good business reasons why people should start paying attention to this issue. "You don't want to be left behind on a fixed sized network in an Internet 'backwater'" says Curran.