How Google judges sites on their ‘freshness’ signals?!

There’s a new Webmaster Help video from Google’s Matt Cutts where he talks specifically about freshness as a ranking signal. The video is a response to the following user-submitted question:

“Google has expressed in the past that frequently updated pages get a boost in rankings (QDF), that seems to favor blogs and news sites over company sites, which have less reason to be updated often. How important of a signal is “freshness”?”

Here is the Video: http://www.youtube.com/embed/o4hH4ZQ_19k