Ask HN: Do You Use JSON-LD, Schema or Open Graph?

Hard to know which semantic metadata to put on a website nowadays.

Which one do you use, and why?

I guess this comes with sub-questions:

- Do you use several?

- Which 3rd party service parses which one?

- What format has the more descriptive capabilities?

- And does it even matter? What are the real consequences of picking any?