But I Like My Solution!
You may be wondering why having so many choices for IPv6 configuration is a problem. In a perfect world, it wouldn't be. Each one has its own advantages and disadvantages, and makes more sense in some situations than the others.
Unfortunately, they are not all equally well supported across operating systems. Most largish companies now have a mixture of Windows, Mac, and *NIX systems. Having to deploy a different configuration solution for each is a problem.
At the moment, that's exactly the situation that businesses trying to deploy IPv6 find themselves in. For example, Windows 7 supports DHCP6, but doesn't support getting DNS server addresses from the router advertisement. If you set up a *NIX network using radvd, then your Windows machines won't be able to find the DNS servers[md]or, more likely, will only find them via IPv4, introducing some of the problems that we looked at last week.
OS X, as of 10.6, doesn't support either mechanism, so you probably have to manually specify the DNS address on every Mac on an IPv6 network[md]or continue to use IPv4 for DNS, even if you use IPv6 for everything else.