While people say “IPv6 is just like IPv4″, there are a lot of changes. If you read really, really old documents about IPv6 (consider it’s come of age) you will read statements like “IPv6 adds Mobile IP, IPsec and a lot of new features to the TCP/IP suite”. This is no longer the case, as many of the features where “backported” to the good old IPv4.
There are still a lot of news that you need to get an overview of before you get your IPv6 Tunnel or a real IPv6 network from your Internet Service Provider. There are a lot of good starting points on the net. Here’s a few from the IP address registries and the Internet Society. Of course, make sure you visit your vendor’s IPv6 resource pages. If they haven’t got one, please do remind them!