This is great news on several different levels. Semantic markup within web pages provides a way to target searches much more effectively. TechCrunch provides an excellent example:
“If I was to write a post that mentioned “The President” without naming him, Google probably wouldn’t realize that I was talking about President Obama – it might think I was referring to another US president, or perhaps the leader of a company. But using RDFa I could tag the words “The President” with “Barack Obama”. That tag would be visible to machines spidering the page for indexing (resulting in smarter search results), but wouldn’t be shown to users reading the post. In effect, it’s a way to tell search engines about your content without exposing your visitors to extraneous text.”
In addition, sites that provide well-structured metadata have the potential to be much more usable (and useful). Library web sites, especially OPACs and Resource pages, should include structured information that details the context of the displayed content. Using microformats in our web sites will benefit everyone involved over time. As David Peterson notes on the SitePoint blog:
“Now that Google is supporting structured data it is high time to learn how to use this stuff.”
