— Eric Enge and Stephan Spencer and Jessie Stricchiola and and Rand FishkinGoogle refers to this concept as query deserves freshness (QDF). According to the New York Times (http://www.nytimes.com/2007/06/03/business/yourmoney/03google.html?pagewanted=3), QDF takes several factors into account, such as: Search volume News coverage Blog coverage Social signals from Google+, Facebook, Twitter, and other sites Toolbar data (maybe) QDF applies to up-to-the-minute news coverage, as well as to other scenarios such as hot, new discount deals or new product releases that get strong search volumes and media coverage.
Replicated under Fair Use from The Art of SEO by Eric Enge and Stephan Spencer and Jessie Stricchiola and and Rand Fishkin.