One of the greatest aspects of social media is it's transparency. It opens up dialogue between businesses and their customers. Not a one-way dialogue, but a very open engagement which sends messages that your businesses is approachable, has a personality and is open to their comments, concerns and needs. All this helps to build trust, confidence and loyalty.
Today the most common approach to seeking information is through Google. Tomorrow it could be that your potential customers will ask a question to their thousands of followers on Twitter or it' successor instead.