I understand why blizzard has decided to not recognise the tunnelers and psuedo IPv6 addresses during the tests, but i hope in time they can implement their servers to recognise these protocols as im sure a lot of people in the public and business sector will want to take the easy way out in the shorter term.
Having a clear pure IPv6 service across the net will be a great help for the long term, but in my opinion it will slow down the process of conversion to widely used IPv6
Not trying the auto-tunneling protocols is probably the best course. They can be handy, but they can also be almost impossible to debug. 6to4 works by trying to send final v6 destinations to the closest instance of 22.214.171.124, and traffic from v6 goes back to the nearest instance of 2002:/16. Teredo jumps through a ton of hoops to try and get around NATs, then tries to discover relays. If every ISP ran 6to4 and Teredo relays, this might be workable, as the traffic would have a pretty deterministic path, but they don't, and have to go through random networks and commonly suboptimal paths to get there. As such, trying to support it from Blizzard's side would be a nightmare. Network operators aren't fans of them, as they're yet another stopgap measure when people just need to GO NATIVE. The only true solution is native. In the meantime, configured tunnels (which WoW is supposed to be happy with) are at least able to be troubleshot in a reasonable manner, since where everything is going and coming from is pretty easy to nail down. There's also no element of user surprise, since someone had to set the tunnel up.
Realistically, we'll see dual-stacked networks for a while. The pain will begin when sites start going only IPv6, and then we'll start seeing 4to6 relays... with all the fun of the above, all over again.