IPV6

http://lists.arin.net/pipermail/arin-ppml/2009-January/012900.html
Matthew Petach wrote:
It's a very tough sell to pitch to your customers: "hey, the future is IPv6; come sign up for our future-proofed dual-stack offering; it still burns IPv4 addresses, so it doesn't help the runout period, but at least you can connect to all 131* sites that support IPv6 at the moment; unfortunately, you'll have longer connect times as your DNS resolver attempts to fetch quad-A records first, and then falls back to seeing if there's A records for the site, and if a site returns a quad-A record but the v6 connectivity isn't working, you'll just be broken, it won't fall back to using v4, so you'll have an overall poorer experience than your v4-only neighbor; but it's the future, so you should sign up now!!!"