Manu Sporny is one of the editors of the JSON-LD specification, which is JSON for Linked Data, a term coined by Tim Berners-Lee in 2006. Since it is a simple extension to JSON, it is promoted as a simple serialization format for web developers to adopt.
JSON-LD is used by schema.org, which is a library used for structured markup of web pages to provide information to search engines such as Google, Yahoo!, and by Mozilla Science Lab in their code as research project. It is also being considered by the badge alliance a spinoff of Mozilla's Open Badges for badge portability and interoperability with additional data in other places on the web(Also see Nate Otto's extension proposal on the W3C Credentials Community Group Mailing List as well as Manu Sporny's recent review). An overview of JSON-LD is provided by Manu on Youtube.
Manu has spoken at various venues globally including the 2nd Google Edge Conference in New York City, the Internet Governance Forum, W3C's first Payment Workshop,the Bay Area Node.js Meetup, as a keynote speaker at the 2014 Semantic Technology and Business Conference, and others.
One way to get involved with Manu Sporny is to join the W3C Credentials Community Group or the Web Payments Community Group, or just jump on a weekly/monthly conference call :). You can also find him in many other places with the W3C such as the Web Payments IG.