Given the giant packet header sizes for Ipv6s authentication standards, migrating to its either going to mean new uber-fast networking equipment (eg routers and switches with very fast processors and lots of large memory cache and RAM), or it's going to mean you get to experience the joy of retro-surfing - or I suppose it means you just disable or otherwise don't use all the new features and just take advantage of the very long IPs.

Say goodbye to being able to remember IP addresses.