I read this article today at AdAge.com and found it quite interesting.  While it is not focused on Local Marketing, it is representative of the changing nature of advertising in general.  

Old Spice created a campaign called "The Man Your Man Could Smell Like".  The spot ran on television and then created quite a stir on YouTube.  In fact the response was so strong that Old Spice decided to capitalize on it and create some very raw responses from the actor - including this one:  
This series of responses has generated more than 42 million views on YouTube - essentially for free.  The combination of paid and viral media is difficult to get right, but when you do the effect is powerful.