Twitter can be used effectively in marketing in several ways: 1) As a customer service platform to provide support and answer questions. For example, Best Buy's "Twelpforce" program. 2) As a collaboration platform to help customers work together to solve challenges or help each other. 3) To develop personal brands for key employees and leaders in professional services and other people-focused businesses, as the value of an organizational brand is influenced by the personal brands of its people.