Few companies are utilizing succefully relationships with customers in facebook.
Companies need to build repo with the visitors of fan page regularly and these marketing tips might be helpful for some of you.
1) Always create two way conversations with the people visiting facebook fan page. They like most of your words and visit again and again and share your services with other friends.
2)Ask them ( visitors ) to share about or give opinion about your products or services by creating Polls and asking questions to them.
3)Content you are sharing with the visitors should be more attractive, title makes possible everything.
No one like to share bored content.
4)Be creative, by gathering the opinions from the visitors improve your products and services. Before releasing any thing you can ask for reviews from the fans.
All the best