I don't think that Social Media is the silver bullet, as this video seems to imply. However, it is still a force to recon with. I am particularly excited about it's potential for small to medium size businesses, who get to advertise for free.
There seems to be no better example of a small business using social media, than Kogi BBQ , the Mobile Barbeque business. The company operates a fleet of vans that drive around, and post the location where they would be stopping 45 minutes before they get there. When they arrive, there is already a line of people waiting to buy food from them. These are the kinds of ideas I look at, and say 'Brilliant!!'