Creative machines: How close are we to AI-generated content marketing?

We typically think of artificial intelligence (AI) within our industry in terms of processes and calculations. Media buying, for example, is ripe for intervention by sophisticated algorithms and machine learning systems. The commonly-held assumption is that developments such as these will free up humans to spend more time on creative tasks, like campaign strategy and content production. But as we move from rule-based automation to true AI, should we believe that creativity will remain a singularly human pursuit? How close is artificial intelligence to being able to carry out the role of a content marketer?