Well... if every Chinese and Indian want their own static IP, we'll probably run into problems. And because NATing wasn't done originally and some organizations were assigned too large blocks, and because of some of the reserved/non-routable blocks, it is a problem. But imho not as big a problem as some people are trying to blow it up to be.
Would be nice if we could wave a magic wand and make the entire internet (and all applications) IPv6+IPSEC capable at once. But it doesn't really work like that... also, protocol overhead increases, and good luck trying to memorize IPv6 addresses
Spot on f0dder
The degree of complexity IPv6 introduces doesn't offer enough "benefit to grief" for it to be happily embraced by most organizations. Especially when IPv4 and NAT works so well for internal use. Content providers (telcos, movie studios, e-commerce providers, etc.) are all chomping at the bit because they envision a whole new range of products and services they could be selling
with an expanded address space.
The rest of us could probably care less.
I strongly suspect what will ultimately happen is that IPv4 will continue to be used on most internal networks. Those addresses will route out via a new NAT schema to IPv6. IPv6 addressing will only be used where it is actually required, such as the Internet backbone. Newer routers will be built to arbitrate between the two different address schemes.
Probably the only major change will be that all
IPv4 addresses and subnets (0.0.0.0 thru 255.255.255.255) will become the new private non-routable address space.
Yay! No more 192.168.x.x/24
There has been some talk of eventually getting the governments to enforce the use of IPv6. I don't see that happening any time soon. The costs involved in forcing that significant a change onto the world's infrastructure doesn't even bear thinking about. And all it would take is one major holdout to end the discussion. That holdout could even emerge from the grass roots level. Much like back in the early 70s when the American public and business community refused to adopt the metric system despite all the efforts of the US Government to persuade them otherwise.
IPv4...IPv6...why choose one when you can have the benefits of using both?
We'll just let the backbone, internal routers, and DNS handle the details for us.
And why not? That's what we built the little buggers for to begin with!