Google announced yesterday a new supported structured data format named Q&A pages. It is designed to help Google with the question and answer formatted snippets carousel, where they let you slide through answers to questions from Q&A pages.
Google has been showing these best answer carousel snippets for about a year or so now. Now Google has published official structured data markup for it.
You can access the new markup over here, it says:
Q&A Pages are web pages that contain data in a question and answer format, which is one question followed by zero or more answers to the question. For content that represents a question and its answers, you can mark up your data with the schema.org QAPage, Question, and Answer types.
Properly marked up pages are eligible to have a rich result displayed on the search results page. This rich treatment helps your site reach the right users on Search.
This is designed for social news sites, expert forums, and help and support message boards are all examples of this pattern. Here are some screen shots of this in action:
Forum discussion at Twitter.