Short-form social network Twitter has taken a bold new step in exploring its potential business model. The company appears to have begun promoting keywords in its “trending topics” list for sponsors.

When users click on a promoted trending topic, they are brought to a search results page, where the page is topped by a promoted Tweet. They aren’t sent to an ad landing page, but to a live and uncensored conversation. That’s what we’re seeing with the new movie Toy Story 3 today at least. It’s a logical and interesting way for the company to make money. It’s also unlike almost any other advertising in history.

Twitter announced its promoted Tweets search results program this Spring and social network watchers have been waiting to see promoted Tweets appearing in the middle of users’ streams. Tonight’s inclusion of sponsored trending topics may be the closest thing we’ve seen yet. The company hasn’t yet responded to our request for comment on the new program.

Recent research from HP found that the level of Twitter chatter about a movie could do a better job predicting that film’s box office performance than leading industry methods – so perhaps it’s no co-incidence that a film was first to put down money to increase the chatter.

How These Ads Are Radically New

It’s cool that the links aren’t just links to advertisements, but to the real-time conversation (good and bad) that users are having about the topic. Sponsorship is just a way to influence and increase the profile of the conversation about a product, without controlling it. That’s a radical proposition and one that would only work for brave or lovable sponsors.

BP has spent millions of dollars buying Google ads for search terms like “oil spill,” for example, but is very unlikely to spend money promoting the Twitter conversation about its brand or related topics.

So what about your company? Are you brave enough to buy an ad that would propel open-ended public conversation about your company towards the front of mind for tens of millions of people?