Zef Hemel announces the opening of a new office and discusses his company Cloud9, a JavaScript IDE built using open source technologies like Node.js, HTML5, and CSS3. The IDE allows code to run directly in the browser or on cloud servers, and supports collaboration and integration with cloud services. Key features highlighted include debugging, source control, deployment, and using cloud computing resources. Cloud9 is also released as open source software and contributions are welcomed through the company's GitHub page.