A new article on building CouchApps (using CouchDB) is available on IBM developerWorks:

Apache CouchDB is an open source document-oriented database management system that allows you to create full database-driven applications using nothing but HTML, CSS and JavaScript. In this tutorial, you will learn how to create your own CouchApp that will perform database operations using Ajax powered by the jQuery framework. The application you will build is a contact manager that allows you to view, create, edit, and delete your contacts.

Read Building CouchApps