Fine line between Content & Ad

The days of clear difference between an ad (or promotion) and regular content is nearing an end. As I see it, there are 3 different groups…
1. Google very clearly demarcates an ad as an ‘ad’ or ‘sponsored link’ in almost all its properties. How long this will last is anyone’s guess.
2. In Facebook, there is a very fine line between regular UGC and ad content. That’s why advertisers love it.
3. In Print, I realized, almost everything can be an ad. You pay, you manipulate content. What I fear is these print guys coming online bring this thought with them.