Digital marketing is evolving as fast as any other medium on our tablets, smartphones, Google Glass and beyond. To learn about what the future may bring to this marketing genre, we reached out to Gerd Leonhard, an author, strategic advisor, CEO of TheFuturesAgency, and someone whom The Wall Street Journal calls "one of the leading media-futurists in the world." Here are some of Leonhard's predictions for what's coming. Add yours in the comments section below. 1. By 2020, most interruptive marketing will be gone. Instead, marketing will be personalized, customized, and adapted to what I have expressed as my wishes or opt-ins — which essentially means that advertising becomes content. Data will be essential, and as users, we'll be paying with our data — bartering a bit of our personal information in return for the use of platforms and services. Customers will be forming relationships with brands that are built on trust, and if a company breaks that trust, it will be very quickly viral and very quickly over. By 2020, unauthorized targeting of consumers will essentially be useless. I, as a consumer, am going to choose who I want to hear from. I'm going to like things, or I won't like them, and you will have to earn that from me. Get the full story at Harvard Business Review