A very informative and entertaining presentation by Scott Davis of ThirstyHead on using RDFa and Microformats to build services that are OF the Web, not just ON the Web. Presentation slides can be found here.
Another excellent blog post by Chris Silver Smith: Brave New World For Yellow Pages: Google Nabs Marketshare, Strangles Local Directories, from September 2009.
Also see the following related posts from Chris Silver Smith:
- Why Use Microformats?
- How To Geocode An Address & Optimize Location Pages
- The hCard Microformat & Local Search Optimization
- Optimize Local Events With hCalendar Microformat