After companies like Yahoo and Technorati have no experimented for quite some time with support for Microformats, Google announced their own support for some Microformat and RDFa vocabularies. According to James Turner of the O'Reilly Radar this only works for a handful of partner-sites right now but, I guess, this should only be a matter of time. For now the supported metadata is about product reviews, product prices and personal details. Google's made some more details available in their documentation.
What's in my opinion really nice about this is, that Google supports not just one encoding but Microformats and RDFa. If you ask 3 people how to handle metadata on the web, you'll probably get 3 different answers ;-)