Google just announced an upgrade to their algorithm that should produce "fresher" results.  That means that content and more specifically NEW content truly is king.  If your website has been ranking based on articles and blog posts that you made a year ago, you can expect a big drop soon.

Have you ever looked up an yearly event and had past years events come up instead of the current one you are attending?  For instance, the Anoka Halloween Parade happens every year but the exact dates and events always change a little.  If I type in Anoka Halloween Parade, I want to see the 2011 calendar not the 2008 calendar.  

If there was a topical event, say a bench clearing brawl during a Yankees game last week the search will assume that i mean the recent brawl and not one from 1996.  

Basically, it is intended to improve the search experience.Google says that the algorithm change will make a 35% difference in current searches.  That's a BIG change!  Now, as with any change, you can expect that there will be internet marketers that try and work around the  change but the best practice is to constantly be creating some sort of relevant content to your business.

It doesn't have to be a novel but it should be original and topical.

Watch your own rankings.  If you see a sudden drop off...you know where to start! 

Read the full Search Engine Land article