One of my initial suggestions to steem was to introduce optional advertising (to any user that wants to opt-in) to break the closed-loop economy with some new revenue stream.
Around two weeks ago I realized my suggestion was redundant, in that advertisers could simply use Steem Power to do their work. The closed-loop economy isn't as closed as I initially thought it was because advertisers can buy advertising power (steem power) instead of ad placements. And this power can be deployed in a multitude of ways.
This is the exact reason why we feel so strongly about steemit because it puts the advertising dollars directly in the hands of the content creators and not the middle man.