In an interview one of the designers of IPv6 admitted that they should have made it backwards compatible
. Hindsight being 20/20 and all that.
The impression I get (since I'm part of the group that runs the network for a major southeastern university) is that everyone should be running dual-stack for a while. Any infrastructure equipment you get that runs v6 should also be able to run v4 fairly easily. Any time we upgrade all the equipment in a building, or put in a new building, the addressing for the switches gets done via IPv6. For a majority of desktops, dual stack is available. For servers
... it depends (the issues there being more human than technical).
But we have the money available to us to have IPv6 capable equipment. At home, FiOS has yet to provide me anything that provides IPv6 connectivity natively (ignoring tunneling). From what I've ready recently, say what you will about Comcast, at least they're deploying it.
The impression I get from your post is that you have equipment (both infrastructure and otherwise) that's more than 10 years old. I feel for you; we do, too. To a large extent, I'm not so sure you want an OS that old to have any kind of Internet access anyway. From a "It makes me feel good" stand-point, it would be nice if there were an easily implemented v4-v6 translation method available, but there just isn't.
So, what am I trying to say? Well, I've never talked to the "IPv6 crowd," but I don't doubt that they can be obsessive. But need to maintain an internal IPv4 network? Oh my, that can't be that hard. IPv4 isn't going away any time soon, and I seriously doubt there's anything out there on the services side (IE, a website) that you couldn't easily get to via IPv4 (unless it's an IPv6 proof of concept site).
It's going to be outside-in. Until all the major providers of home internet are providing at least a majority of their customer base IPv6 access, it's not going to be that big a deal. And even after they're doing that, you've got to assume that they'll be dual-stacking it, too. At least for a while.