Ok so the main purpose of Microformats and RDfa are to solely help people find information easier on your website. That's understandable. But I dont think it's caught on that much yet. I'm using hcard but I have VERY little click throughs on it.
Marignally (indirectly) may be because of better structure and more people will link to your site. My overall principle,
make it simple, as simple as possible but no simpler.
Content is king. Refactoring to better code and structure is Queen.
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