The idea of ads indistinguishable from content is troubling. I agree this is a probable outcome. It sounds like food for conspiracy theories. I see two paths. First, ads so good you seek them out knowing they are advertising. This would be similar to a good catalog. Second, you are looking for content and find something produced by a company without your knowledge. It would be easy to produce "Top 10" lists or other style of content that favors your products. In that scenario, trust becomes the valuable commodity.