Seconded. IPv6 brings a lot of nice things that we never would have had in an IPv4 based or extended world. Router fragmentation? Gone! Simple subnetting? Hello

Seconded. IPv6 brings a lot of nice things that we never would have had in an IPv4 based or extended world. Router fragmentation? Gone! Simple subnetting? Hello ipv6! DHCP? Gone (mostly)! Link local addresses? Got em! These are all positive things we wouldn't have if we were still clinging to IPv4.