Before all the haters (pot, kettle, black - i know) tire themselves out jumping up and down about how awful change is, please take the opportunity to educate yourselves about this.
Perhaps the best person to explain why IPv6 is necessary is the man credited with the majority of the work involved in developing IPv4 Dr Vinton Cerf (known in many circles as "the father of the Internet"). He spoke recently at
linux.conf.au, and discussed many challenges facing the open Internet, including the exhaustion of the IPv4 address space. You can find that talk
here. I'd encourage everyone who has an interest in the Internet to seek out videos of other talks he's given on the subject.
There's another, by John Curran, President and CEO of ARIN (The American Registry for Internet Number, the corporation that assigns IP addresses within the United States) given at DEFCON 18 that also explains quite well how IPv6 is going to work. That video can be found
here.
For those interested in what adoption will involve, I recommend following
Hurricane Electric's "certification" program. It walks you though the main aspects of implementing IPv6 connectivity, and you get a free t-shirt at the end.
In trying to keep this from turning into a flame war I'll leave it to you guys to check out the links above and see if you can wade through the FUD to reach a sensible conclusion.
Ehtyar.