As a preparation for the change and starting today, Search Console will issue warnings for pages using the data-vocabulary.org schema so that you can prepare for the sunset in time. This will allow you to easily identify pages using that markup and replace the data-vocabulary.org markup with schema.org.
A bit more about structured data
Google uses structured data standardized formats and shared schemas to provide information about a page and the things described by the page. This information is used for two main purposes
Understand the content of the page
Enable special search result features and enhancements
What are structured data formats?
Structured data formats like JSON-LD, RDFa and Microdata define a small number of fixed structures that can be used to encode descriptive data. They typically build upon lower-level standards like JSON and HTML. To learn more about the supported and recommended formats, please check out our developers guide.
What are structured data schemas?
Alongside the structured data formats, structured data schemas work like a kind of dictionary, defining terms for types of thing (e.g. “Person”, “Event”, “Organization”), and for properties and relationships (e.g. “name”, “worksFor”). By maintaining this separation between format and schema, it is possible for users of different formats to take advantage of the same, widely shared, schemas.
Google’s “Data Vocabulary” project was an important milestone in the development of structured data on the Web, because it led to our collaboration with other search engines to create schema.org. However it is now very outdated and it is generally preferable to use more widely shared vocabulary from Schema.org. Therefore data-vocabulary.org markup will stop being eligible for Google search result features and enhancements.
Please note that this is the only consequence of this change. Pages using data-vocabulary schema will remain valid for all other purposes.
In order to be eligible for Google rich result features we recommend converting your data-vocabulary.org structured data to schema.org.
For example, here is how you would change the data vocabulary to schema.org
Posted by Dan Brickley, Standards Developer Advocate, and Moshe Samet, Search Console Product Manager