The advent of Web 2.0 and its collaborative tools (forums, chat, blogs, wikis) simplified the interaction among various business subjects (company, customers, suppliers). A new model of Enterprise 2.0 communicates interactively with all stakeholders, cooperate with them, listen, create, share and capitalize knowledge. Web 2.0 enhances customer relationships and supports, fully, developments in the field of marketing: from advertisement to participation, from social networking to mobile communication. In this paper we talk about Marketing 2.0 that with interactive web 2.0 tools facilitates the relationships between enterprise and customer. The enterprise communicate with customer, by a bidirectional channel, during pre and post purchase. The customer affections sentimentally and emotionally to brand and company. The enterprise can know, in real-time, reviews of customers on product/service and the degree of satisfaction and behaves accordingly. Marketing 2.0 leds companies to reach business goals using technological tools and social media that exploit, in the interactive dialogue, the old power of word of mouth.