Microformats are a relatively new phenomenon on appearing in search engine results pages.  They are highlighted by a star rating which appears on the first line under the actual result, and may indicate a review, person or event connected to the search term. Google calls these ”rich snippets”. This article from Wordtracker, concludes that the inclusion of snippets will improve the clickthrough rate of the displayed page, and suggests that these could be used in the Google algorithm. The article then gives some helpful tips you can use to mark up reviews on your page that will attract Google’s attention.