The telecom folks have been reminding us of the depleting space in IPv4 for years, but have we listened? Probably not enough, because at just 40 years old, IPv4 is about to max out the number of addresses it can track, and many companies are still working on the transition. Remind anyone of Y2K? It should, because it’s basically the same root cause: We built architecture around a certain format without thinking ahead. It’s a bit easier to understand that when they were experimenting with a 32-bit address back in the ‘70s, no one would ever imagine that the Internet would become what it is today.

Industry pundits are calculating that addresses will run out sometime in 2011. Major Web-based companies are committed to adopting IPv6, but without global adoption, we’re living on borrowed time.

According to Forrester senior analyst Andre Kindness, there are three technologies to enable IPv6 transition: Dual-stack, tunneling and translation. From my informal polling at last week’s Forrester IT Forum, it sounds like most CIOs are going with the dual-stack method — allowing IPv4 and IPv6 to coexist on the same devices and networks — as the path of least resistance. But everyone should have a plan at this point.

Consider World IPv6 Day as your call to action. Use this as an opportunity to test your systems on the new world order. You can go to Test-ipv6.com before June 8 and check out how well your systems will do in preparation to sample the IPv6 wares from corporate giants like Google, Cisco, Facebook, VeriSign and Akamai, among others.

Of course, the world’s population is approaching 7 billion people, and IPv4 had space for about 4 billion addresses. IPv6 has space for trillions of addresses. It should be a while before we run out of 128-bit addresses. Knock on wood.

What’s your game plan for World IPv6 Day? The comments are dying to discuss your strategy.