Web 2.0 defined

Richard McManus points to Wikipedia's definition of Web 2.0. The definition lists a number of technologies/techniques that make for a 2.0 site.

Technical:

• CSS, semantically valid XHTML markup, and microformats
• Unobtrusive Rich Application techniques (such as AJAX)
• Syndication of data in RSS/ATOM
• Aggregation of RSS/ATOM data
• Clean and meaningful URLs
• Support posting to a weblog
• RESTian (preferred) or XML Webservice APIs
• Some social networking aspects (share your data with friends, etc)

General:

• The site should not act as a "walled garden" - it should be easy to get data in and out of the system.
• Users should own their own data on the site
• Purely web based - most successful web 2.0 sites can be used almost entirely through the browser

What would it take to make our church websites "Web 2.0" sites?