One way to kick start IPv6 is to try and convince the likes of google to rank IPv6 accessible web sites higher than IPv4 sites.
They don't have to say how much higher or anything, just make it a published factor in the ranking.
I suggest they give the world a couple of months notice so people do not whinge, though no special reason they have to.
As soon as they do this we will have a mad scrabble to get web sites enabled on IPv6 to increase peoples rankings. There will suddenly be commercial pressure on hosting companies to provide IPv6 access (hence it would be nice to give a bit of notice).
Obviously these hosts would be dual stack for now, but it would make a big chunk of the internet IPv6 accessible, and would push deployment of IPv6 routers and firewalls and servers.
It is not the whole battle - you have to get consumers moved over too, but it is a big step forward. One side will have to move first.
So, google, please rank IPv6 hosted sites higher - simples.
Of course, if google won't do this we just need to start an urban myth / rumour that they already do it or are about to do it and are keeping it secret. The myths and rumours about search engine ranking are mad enough already this would be quite believable.
As someone else said, this close to Y2K we had massive take up and everything was "Y2K compliant" even toasters. We have almost no take up with domestic router manufacturers and are now only a few months away from trouble...