> IPv6 is a big deal though. Everyone's going to have to touch their long-running servers sometime before the end of this year. With IPv6 Day closing in this June and the eventual migration of residential broadband to IPv6, this is one of those inevitable things that isn't going to magically go away.

I think you're confused about the implications of the IPv6 transition -- IPv4 is a subset of that address space, so existing servers will "just work" via Carrier-Grade NAT that ISPs are providing.

Some tiny percentage of the Internet is IPv6 reachable today, and it ain't all gonna change this year. The IPv4 space can't turn into a parallel ghetto Internet after all...