Facebook's attempt to exploit its social network for advertising purposes has raised some major concerns from their users. The Beacon advertising platform is designed to broadcast purchases made by users to their social network. The issue has been taken up by the progressive political organization, MoveOn.org claiming the program violates privacy. Over 50,000 Facebook users have signed the MoveOn.org petition complaining about the privacy issue. The primary problem seems to be in the opt-out strategy taken by Facebook. There is no question that social networks are here to stay and they do influence purchases, especially for travel. The "Where I've Been" application (now owned by Trip Advisor) has been one of the most successful applications on Facebook. Behavioural targeting is also becoming a mainstream advertising strategy that is designed to deliver specific content based on the implicit and explicit behavior of the user. Earlier this year one of the largest players in the behavioral targeting space, Tacoda, was purchased by AOL demonstrating the importance of this emerging advertising trend. Mobile advertising is beginning to become major force as well. Whether planning a complex vacation or buying a HDTV, the opinions of my friends and colleagues do make a difference. The key lesson here is that no matter what the platform (social networks, behavioural targeting or mobile advertising) the user must be in control. Opt-in is the key, not opt-out.