that is because an IPv6 address is 128 bits long compared to the current 32 bit long IPv4.
This is analagous to "you don't have to understand water to stand in the rain and get wet". If the IEC gets its way, IPV6 will become the standard. But the fight has been going on for several years now and we still seem to be doing nicely with IPV4. BTW, XP SP1 or 2 loads IPV6 by default. Boy, I just love doing an "ipconfig /all" and seeing all those 128 bit ip's.
I thought they were saying now that in five or six years they were going to start running out of IPv4.
I think it is something that we should start thinking about. I would predict that in ten years, the number of devices we use that will connect to the internet independent of a router (meaning that they will have their own IP address) will increase.
Mac OS 10.6.7 - Personal Ubuntu Server 11.04 - Server
With cell networks in the US (and the rest of the world nearly there already most likely) going to a more IP-based web setup than it currently has, I'd guess that in 5 years at the most IPv4 will be overused. The only thing that is really keeping it alive still are the private IPs that can be handed out over and over and over basically, allowing some ISPs to have significantly more traffic via NAT than they could have if every computer had it's own public IP.