IPv6 will be very slow in coming, and there will be no crisis. As ISPs run our of v4 address space, they will offer natted rfc1918 space by default, and charge a few dollars extra for public addresses. Only a few people prefer a public address if charged $5/month for it, and they won't miss anything either. While lots of public servers will be offered in both v4 and v6 space, nothing interesting will require v6. v6 will grow slowly based on its use in purely internal networks. The things lusers need will always be available in v4 and there aren't enough clued users to create a real shortage.