[bipson]

Even at organizations that have considerably smaller networks than Google, Amazon, Facebook and Co there are just seemingly insurmountable numbers of "small" problems that discourage all the involved parties to adopt.

We had IPv6 at our research area 10 years ago. Admins changed, and it was wind down bit by bit, because "it made problems". Not only that, I learned that the the general view over all of the admin-staff in our organization (a larger "Technical university" in Europe) agreed that IPv6 "makes problems" and nobody wants it.

Change is painful...? It is a shame, but what can you do?