Thought leadership, branded content, content marketing, and native advertising are all stops along the continuum of how ideas are expressed, and products are marketed over the Internet. But it is getting awfully hard for the public — and even some marketers — to tell the difference. But in a culture that is thin on trust, and sometimes demanding transparency, social media marketers are beginning to take more heat for blurring the lines between promotion and objective information. Regulators are beginning to catch up, too, and there are more regulations waiting in the pipeline. Our suggestion: Make sure your content sponsorship is easily distinguishable.