Voice Over IPV6 is under construction and it will always be :)

Why Voice Over IPV6? These days voip at enterprise is quite popular, and enterprise networks do not seem to need ipv6. However I am expecting that in the near future voip will gain traction in the service provide area. Those networks will go beyond ipv4. Just imagine a country with 50 million ip enabled mobile phones running SIP. Imagine 20 million homes with internet TV. Perhaps your TV set will have either an IP enabled set-top-box or the TV will have ethernet port and a builtin webcam and microphone.

I thought I heard you saying "I'll call home from my mobile phone for a video call"  or do you like to call your cousin in the UK from your home IP-TV with integrated video conference device? That's that day when we will have voice over ipv6. Already all new TVs have SMARTTV.

Enterprises will continue running ipv4, probably in dual-stack mode, or to retain the good old commonly used ipv4.