There is no Data Vault 3.0 and hopefully never will be. Data Vault methodology and modeling is an ever evolving with its growing user community. There are certifying bodies for Data Vault with well known authority to guarantee quality of the certificates.
Dan Lindstedts Data Vault 2.0 number designation from 2012 is not a Data Vault industry version but rather represents one flavour of Data Vault that could be used. The principles of Data Vault modeling do not differ depending on the flavour you decide to deploy. The reason to brand a 2.0 is to take ownership of a locked down version of Data Vault and monetize it. As everyone know; as soon you lock down a technology it’s obsoleted. Data Vault has fortunately never got stale or obsoleted but is continuously improving and evolving.
The fundamentals of Data Vault modeling are very stable although there are some areas that are been fine-tuned over time. The Data Vault modeling taught and used on the market should strive to be the most current understanding and active industry best practices.
The community doesn’t use number designations on Data Vault modeling. However its good to present and discuss some commonly understood highlights that has been adopted into a few of the flavors (including Dan Lindstedts Data Vault 2.0).
But it is a bit unfortunate that the launch of 2.0 has caused confusion in the industry. The messaging can get a bit misleading and it is not difficult to see how this can shake people up. Keep in mind that Data Vault modeling has been a commercially viable approach for 15 years with the first deployments in the government and financial markets industry. Over that period of time there have been over 1000 data warehouse projects that have selected to work with Data Vault. During this whole time and even more so since 2012 refinements have been made and it is fair to say that each new adopter takes advantage of lessons learned through the experience gained by the other deployments. This is all captured in the most current versions of the Data Vault community and certifying bodies.