As I wrote elsewhere some time ago:
IPv6 is the Windows Vista of networking. Or possibly the Windows 8. Yep, it's got all the features, yep, it is technically miles ahead of what went before, yep, it is very clever, yep, it's got loads and loads of gee-wiz new features, and yep, everybody hates it because it doesn't work the way they expect it to and it breaks stuff.
IPv6 has failed in the market the way Vista failed. If it was anything remotely like what people wanted, it would have been a huge success by now, but hardly anybody uses it or wants it. Everybody understands IPv4, even your granny can get her mind around it if you make analogies with street addresses and post box numbers. Above all, IPv4 has those non-routable address blocks and with readily available $30 NAT boxes, with only a very basic skill set, anyone can make sure that packets which belong inside the building stay inside the building. Simply, the market does not want IPv6, it wants IPv4 with extra numbers.
To the IPv6 Committee: piss off.
We, the rest of the world, don't want your bloated, over-complicated, intrusive Vista of a product. That's why we have been assiduously avoiding it for longer than we have been laughing and pointing at Windows ME. It's been around and been "about to become the future" since before most teenagers were born, since HTML 4 was an RFC awaiting official approval (never mind XML, let alone HTML 5), since OS/2 was a not uncommon operating system, since Netscape Navigator was high-tech and popular, since search meant Yahoo or Alta Vista, since nine years before the very first iPhone was released, and it still hasn't caught on. That's what we people in the trade call a "hint".
(Sorry for cross posting.)