Facebook is gaining more and more prominence as a business tool. It can help build brand awareness and communications with clients potential clients.
You can set-up Pages and Groups through which you can get your message out.
For our client www.caminio.com we have created an automated Facebook product feeds from their Cubecart powered shop. They have now over 2000 'friends' who receive any new product in their Facebook page automatically. They have confirmed that this has lead to additional sales.